About  |  Kamus SABDA Mobile
Table of Contents -- Sign
POS
WORDNET DICTIONARY
CIDE DICTIONARY
OXFORD DICTIONARY
THESAURUS
ROGET THESAURUS
Link, Gadget and Share
Copy the code below to your site:
Link
Gadget
Share
 Facebook
 Twitter
Add to your browser

Sign

RELATED WORDS :

 : 
Noun, Verb (usu participle), Verb (transitive), Verb (intransitive)

WORDNET DICTIONARY

Noun Sign has 11 senses

Verb Sign has 8 senses

Adjective Sign has 1 sense

CIDE DICTIONARY

Signn. [F. signe, L. signum; cf. AS. segen, segn, a sign, standard, banner, also fr. L. signum. Cf. Ensign, Resign, Seal a stamp, Signal, Signet.].
     That by which anything is made known or represented; that which furnishes evidence; a mark; a token; an indication; a proof.  [1913 Webster]
    " Educaters of the deaf distinguish between natural signs, which serve for communicating ideas, and methodical, or systematic, signs, adapted for the dictation, or the rendering, of written language, word by word; and thus the signs are to be distinguished from the manual alphabet, by which words are spelled on the fingers."  [1913 Webster]
    " The signs are reckoned from the point of intersection of the ecliptic and equator at the vernal equinox, and are named, respectively, Aries (Taurus (Gemini (II), Cancer (Leo (Virgo (Libra (Scorpio (Sagittarius (Capricornus (Aquarius (Pisces ("  [1913 Webster]
    " The terms symptom and and sign are often used synonymously; but they may be discriminated. A sign differs from a symptom in that the latter is perceived only by the patient himself. The term sign is often further restricted to the purely local evidences of disease afforded by direct examination of the organs involved, as distinguished from those evidence of general disturbance afforded by observation of the temperature, pulse, etc. In this sense it is often called physical sign."  [1913 Webster]
    " See the Table of Arbitrary Signs, p. 1924."  [1913 Webster]
    "Through mighty signs and wonders, by the power of the Spirit of God."  [1913 Webster]
    "It shall come to pass, if they will not believe thee, neither hearken to the voice of the first sign, that they will believe the voice of the latter sign."  [1913 Webster]
    "What time the fire devoured two hundred and fifty men, and they became a sign."  [1913 Webster]
    "The holy symbols, or signs, are not barely significative; but what they represent is as certainly delivered to us as the symbols themselves."  [1913 Webster]
    "Saint George of Merry England, the sign of victory."  [1913 Webster]
    "They made signs to his father, how he would have him called."  [1913 Webster]
    "The shops were, therefore, distinguished by painted signs, which gave a gay and grotesque aspect to the streets."  [1913 Webster]
    "An outward and visible sign of an inward and spiritual grace."  [1913 Webster]
Sign manual. (a) (Eng. Law) The royal signature superscribed at the top of bills of grants and letter patent, which are then sealed with the privy signet or great seal, as the case may be, to complete their validity. (b) The signature of one's name in one's own handwriting. Craig. Tomlins. Wharton.
Syn. -- Token; mark; note; symptom; indication; signal; symbol; type; omen; prognostic; presage; manifestation. See Emblem.
Signv. t. [OE. seinen to bless, originally, to make the sign of the cross over; in this sense fr. ASS. segnian (from segn, n.), or OF. seignier, F. signer, to mark, to sign (in sense 3), fr. L. signare to mark, set a mark upon, from signum. See Sign, n.].
  •  To represent by a sign; to make known in a typical or emblematic manner, in distinction from speech; to signify.  [1913 Webster]
    "I signed to Browne to make his retreat."  [1913 Webster]
  •  To make a sign upon; to mark with a sign.  [1913 Webster]
    "We receive this child into the congregation of Christ's flock, and do sign him with the sign of the cross."  [1913 Webster]
  •  To affix a signature to; to ratify by hand or seal; to subscribe in one's own handwriting.  [1913 Webster]
    "Inquire the Jew's house out, give him this deed,
    And let him sign it.
    "  [1913 Webster]
  •  To assign or convey formally; -- used with away.  [1913 Webster]
  •  To mark; to make distinguishable.  Shak.  [1913 Webster]
Signv. i. 
  •  To be a sign or omen.  Shak.  [1913 Webster]
  •  To make a sign or signal; to communicate directions or intelligence by signs.  [1913 Webster]
  •  To write one's name, esp. as a token of assent, responsibility, or obligation.  [1913 Webster]

OXFORD DICTIONARY

Sign, n. & v.
--n.
1 a a thing indicating or suggesting a quality or state etc.; a thing perceived as indicating a future state or occurrence (violence is a sign of weakness; shows all the signs of decay). b a miracle evidencing supernatural power; a portent (did signs and wonders).
2 a a mark, symbol, or device used to represent something or to distinguish the thing on which it is put (marked the jar with a sign). b a technical symbol used in algebra, music, etc. (a minus sign; a repeat sign).
3 a gesture or action used to convey information, an order, request, etc. (gave him a sign to leave; conversed by signs).
4 a publicly displayed board etc. giving information; a signboard or signpost.
5 any objective evidence of a disease, usu. specified (Babinski's sign).
6 a password (advanced and gave the sign).
7 any of the twelve divisions of the zodiac, named from the constellations formerly situated in them (the sign of Cancer).
8 US the trail of a wild animal.
9 Math. etc. the positiveness or negativeness of a quantity.
--v.
1 tr. a (also absol.) write (one's name, initials, etc.) on a document etc. indicating that one has authorized it. b write one's name etc. on (a document) as authorization.
2 intr. & tr. communicate by gesture (signed to me to come; signed their assent).
3 tr. & intr. engage or be engaged by signing a contract etc. (see also sign on, sign up).
4 tr. mark with a sign (esp. with the sign of the cross in baptism).

Idiom
make no sign seem unconscious; not protest. sign and countersign secret words etc. used as passwords. sign away convey (one's right, property, etc.) by signing a deed etc. sign for acknowledge receipt of by signing. sign language a system of communication by visual gestures, used esp. by the deaf. sign of the cross a Christian sign made in blessing or prayer, by tracing a cross from the forehead to the chest and to each shoulder, or in the air. sign off
1 end work, broadcasting, a letter, etc., esp. by writing or speaking one's name.
2 a end a period of employment, contract, etc. b end the period of employment or contract of (a person).
3 Brit. stop receiving unemployment benefit after finding work.
4 Bridge indicate by a conventional bid that one is seeking to end the bidding. sign-off n. Bridge such a bid. sign of the times a portent etc. showing a likely trend.
sign on
1 agree to a contract, employment, etc.
2 begin work, broadcasting, etc., esp. by writing or announcing one's name.
3 employ (a person).
4 Brit. register as unemployed. sign-painter (or -writer) a person who paints signboards etc.
sign up
1 engage or employ (a person).
2 enlist in the armed forces.
3 a commit (another person or oneself) by signing etc. (signed you up for dinner). b enrol (signed up for evening classes).
Derivative
signable adj. signer n.
Etymology
ME f. OF signe, signer f. L signum, signare

THESAURUS

Sign

OK, Roman candle, abandon, abnormality, accent, accent mark, accept, accredit, acute disease, adumbration, advertisement, affection, affirm, affliction, agent, agree on terms, aid to navigation, ailment, alarm, allergic disease, allergy, alphabet, alphabetic character, alphabetize, alternate, alternative, amber light, amen, analogy, announcement, approve, assign, assure, atrophy, attest, attestation, augury, auspice, authenticate, authorize, autograph, back, backup, bacterial disease, badge, balefire, banner, bar, basis for belief, be sponsor for, beacon, beacon fire, beat the drum, bell, bell buoy, betokening, betokenment, binary digit, birth defect, bit, blight, blinker, blue peter, body of evidence, bond, brand, broad hint, broadside, buoy, cancel, capitalize, cardiovascular disease, cartouche, caution light, certify, chain of evidence, change, changeling, character, characteristic, chronic disease, cipher, circulatory disease, close down, clue, colophon, comparison, complaint, complication, condensation trail, condition, confirm, congenital defect, consign, contract, contrail, copy, cosign, counterfeit, countersecure, countersign, course, cue, custos, cypher, data, datum, defect, deficiency disease, deformity, degenerative disease, deliver, deputy, device, differentia, digit, dip, direct, disability, disease, disorder, dispose of, distemper, documentation, donate, dot, double, dummy, earmark, emblem, employ, enchantment, endemic, endemic disease, endocrine disease, endorse, engage, enlist, ensign, ensure, epidemic disease, equal, equivalent, ersatz, evidence, exchange, exchange colors, exhibit, exponent, expression mark, fact, facts, fake, fantasy, fermata, figure, fill-in, flag, flag down, flare, flash, fog bell, fog signal, fog whistle, foghorn, foreboding, foreshadow, foreshadowing, foreshowing, foretoken, foretokening, forewarning, forgo, formalize, functional disease, fungus disease, gastrointestinal disease, genetic disease, gentle hint, gesticulation, gesture, get rid of, ghost, ghostwriter, give, give a signal, give permission, give the go-ahead, give the imprimatur, give the nod, give thumbs up, give up, glance, glimmer, glimmering, glosseme, go light, gong buoy, graph, grapheme, green light, grounds, grounds for belief, guarantee, guaranty, hail, hail and speak, half-mast, hallmark, handicap, heliograph, hereditary disease, hieroglyph, high sign, hint, hire, hoist a banner, hold, iatrogenic disease, icon, ideogram, ideograph, idiosyncrasy, illness, image, imitation, implication, index, indicant, indication, indicator, indisposition, infectious disease, infirmity, initial, initials, ink, inkling, innuendo, inscribe, insignia, insinuation, insure, international alphabet flag, international numeral pennant, intimation, item of evidence, join up, key signature, keynote, kick, lead, leer, letter, lexeme, lexical form, lexigraphic character, ligature, line, locum tenens, logotype, look, make a sign, make over, makeshift, malady, malaise, manifestation, mark, marker beacon, material grounds, measure, metaphor, metonymy, metronomic mark, miracle, monogram, morbidity, morbus, morpheme, motion, movement, muniments, muscular disease, mute witness, neurological disease, next best thing, nod, notarize, notation, note, notice, nudge, number, numeral, numero, nutritional disease, occupational disease, omen, organic disease, pandemic disease, parachute flare, pass, pass on, pass upon, path, pathological condition, pathology, pause, peculiarity, permit, personnel, phonetic character, phonetic symbol, phony, phrase, pictographic character, picture, piece of evidence, pilot flag, pinch hitter, piste, placard, plant disease, poke, police whistle, portent, poster, prefiguration, preindication, premises, premonitory shiver, premonitory sign, premonitory symptom, presa, present, presignifying, prodigy, prognosis, prognostic, prognostication, promise, prompt, proof, property, prophecy, protozoan disease, proxy, psychosomatic disease, quarantine flag, radio beacon, raise a cry, ratify, reason to believe, rebus, red flag, red light, register, release, relevant fact, relief, relinquish, reminder, replacement, representation, representative, reserves, respiratory disease, retain, ringer, rocket, rockiness, rubber stamp, sacrifice, sailing aid, salute, sanction, say amen to, scent, seal, second, second string, secondary, secondary disease, secure, seediness, segno, semaphore, semaphore flag, semaphore telegraph, semasiological unit, sememe, shadow, shake hands, shingle, show, sickishness, sickness, sigil, sign and seal, sign away, sign for, sign off, sign on, sign over, sign up, sign up for, signal, signal beacon, signal bell, signal fire, signal flag, signal gong, signal gun, signal lamp, signal light, signal mast, signal post, signal rocket, signal shot, signal siren, signal tower, signalize, signature, signboard, signifiant, significant, signs, slur, soothsay, sound an alarm, sound the trumpet, spar buoy, spares, speak, sponsor, spoor, stamp, stand behind, stand up for, stand-in, standard, stop light, strike a bargain, sub, subscribe, subscribe to, substituent, substitute, substitution, succedaneum, suggestion, superseder, supplanter, support, sure sign, surrender, surrogate, suspicion, swear and affirm, swear to, swell, syllabic, symbol, symbolization, symptom, symptomatology, symptomology, symptoms, syndrome, synecdoche, take on, telltale, telltale sign, tempo mark, term, the nod, the pip, the wink, third string, tie, time signature, token, tokening, touch, trace, traces, track, traffic light, traffic signal, trail, trait, transcribe, transfer, transliterate, turn over, type, undersign, understudy, underwrite, unfurl a flag, urogenital disease, utility player, validate, vapor trail, vestige, vicar, vice-president, vice-regent, vinculum, virus disease, visa, vise, volunteer, waive, wake, warning, warrant, wasting disease, watch fire, wave, wave a flag, wave the hand, whisper, white flag, wigwag, wigwag flag, wink, witness, wonder, wonderwork, word, worm disease, writing, written character, yellow flag

ROGET THESAURUS

Sign

Writing

VB write, pen, copy, engross, write out, write out fair, transcribe, scribble, scrawl, scrabble, scratch, interline, stain paper, write down, sign, enface, compose, indite, draw up, draft, formulate, dictate, inscribe, throw on paper, dash off, manifold, take up the pen, take pen in hand, shed ink, spill ink, dip one's pen in ink.

Compact

VB contract, covenant, agree for, engage, treat, negotiate, stipulate, make terms, bargain, make a bargain, strike a bargain, come to terms, come to an understanding, compromise, set at rest, close, close with, conclude, complete, settle, confirm, ratify, clench, subscribe, underwrite, endorse, indorse, put the seal to, sign, seal, indent, take one at one's word, bargain by inch of candle.

Security

VB give security, give bail, give substantial bail, go bail, pawn, impawn, spout, mortgage, hypothecate, impignorate, guarantee, warrant, warrantee, assure, accept, indorse, underwrite, insure, cosign, countersign, sponsor, cosponsor, execute, stamp, sign, seal, let, sett, grant a lease, take a lease, hold a lease, hold in pledge, lend on security.

Prodigy

N prodigy, phenomenon, wonder, wonderment, marvel, miracle, monster, curiosity, lion, sight, spectacle, jeu de theatre, coup de theatre, gazingstock, sign, St. Elmo's fire, St. Elmo's light, portent, bursting of a shell, bursting of a bomb, volcanic eruption, peal of thunder, thunder-clap, thunder-bolt, what no words can paint, wonders of the world, annus mirabilis, dignus vindice nodus, natura il fece e poi roppe la stampa.

Evidence

VB be evidence, evince, show, betoken, tell of, indicate, imply, involve, argue, bespeak, breathe, have weight, carry weight, tell, speak volumes, speak for itself, rest upon, depend upon, repose on, bear witness, give evidence, testify, depose, witness, vouch for, sign, seal, undersign, set one's hand and seal, sign and seal, deliver as one's act and deed, certify, attest, acknowledge, make absolute, confirm, prove (demonstrate), indorse, countersign, corroborate, support, ratify, bear out, uphold, warrant, adduce, attest, cite, quote, refer to, appeal to, call, call to witness, bring forward, bring into court, allege, plead, produce witnesses, confront witnesses, place into evidence, mark into evidence, collect evidence, bring together evidence, rake up evidence, experiment, have a case, make out a case, establish, authenticate, substantiate, verify, make good, quote chapter and verse, bring home to, bring to book.

Omen

N omen, portent, presage, prognostic, augury, auspice, sign, harbinger, yule candle, bird of ill omen, signs of the times, gathering clouds, warning, prefigurement, ill-boding, auspicium melioris aevi.

Indication

N indication, symbolism, symbolization, semiology, semiotics, semeiology, semeiotics, Zeitgeist, characteristic, diagnostic, lineament, feature, trait, fingerprint, voiceprint, footprint, noseprint, cloven hoof, footfall, recognition (memory), diagnostic, divining rod, detector, sign, symbol, index, indice, indicator, point, pointer, exponent, note, token, symptom, dollar sign, dollar mark, type, figure, emblem, cipher, device, representation, epigraph, motto, posy, gesture, gesticulation, pantomime, wink, glance, leer, nod, shrug, beck, touch, nudge, dactylology, dactylonomy, freemasonry, telegraphy, chirology, byplay, dumb show, cue, hint, clue, clew, key, scent, signal, signal post, rocket, blue light, watch fire, watch tower, telegraph, semaphore, flagstaff, cresset, fiery cross, calumet, heliograph, guidon, headlight, mark, scratch, line, stroke, dash, score, stripe, streak, tick, dot, point, notch, nick, print, imprint, impress, impression, keyboard symbols, printing symbols, red letter, italics, sublineation, underlining, bold font, jotting, note, annotation, reference, blaze, cedilla, guillemets, hachure, quotation marks, ", double quotes, " ", parentheses, "( )", brackets, "", braces, "", left arrow, "<", right arrow, ">", forward slash, "/", backward slash, "\", exclamation point, "!", commercial at, "@", pound sign, "#", percent sign, "%", carat, "", ampersand, "&", asterisk, "*", hyphen, "-", dash, "-", "_", em dash, "--", plus sign, "+", equals sign, "=", question mark, "?", period, ", ", semicolon, ", ", colon, ":", comma, ", ", apostrophe, "'", single quote, "'", tilde, "~", badge, criterion, countercheck, countermark, countersign, counterfoil, duplicate, tally, label, ticket, billet, letter, counter, check, chip, chop, dib, totem, tessera, card, bill, witness, voucher, stamp, cacher, trade mark, Hall mark, signature, mark, autograph, autography, attestation, hand, hand writing, sign manual, cipher, seal, sigil, signet, hand and seal, paraph, brand, superscription, indorsement, endorsement, password, watchword, catchword, security card, pass, passkey, credentials, open sesame, timbrology, mot de passe, mot du guet, pass-parole, shibboleth, title, heading, docket, address card, visiting card, carte de visite, insignia, banner, banneret, bannerol, bandrol, flag, colors, streamer, standard, eagle, labarum, oriflamb, oriflamme, figurehead, ensign, pennon, pennant, pendant, burgee, blue Peter, jack, ancient, gonfalon, union jack, banderole, old glory, quarantine flag, vexillum, yellow-flag, yellow jack, tricolor, stars and stripes, bunting, heraldry, crest, coat of arms, arms, armorial bearings, hatchment, escutcheon, scutcheon, shield, supporters, livery, uniform, cockade, epaulet, chevron, garland, love knot, favor, beacon, cairn, post, staff, flagstaff, hand, pointer, vane, cock, weathercock, guidepost, handpost, fingerpost, directing post, signpost, pillars of Hercules, pharos, bale-fire, beacon-fire, l'etoile du Nord, landmark, seamark, lighthouse, balize, polestar, loadstar, lodestar, cynosure, guide, address, direction, name, sign, signboard, warning, omen, prefigurement, trace, record, warning &c, alarm, scepter, trophy, gauge, milestone, milepost, brand, fool's cap, check, telltale, test, mileage ticket, milliary, notification, advertisement, word of command, call, bugle call, trumpet call, bell, alarum, cry, battle cry, rallying cry, angelus, reveille, sacring bell, sanctus bell, exposition &c (explanation), proof, pattern, indicating, indicative, indicatory, denotative, connotative, diacritical, representative, typical, symbolic, pantomimic, pathognomonic, symptomatic, characteristic, demonstrative, diagnostic, exponential, emblematic, armorial, individual, known by, recognizable by, indicated, pointed, marked, denotable, indelible, in token of, symbolically, in dumb show, ecce signum, ex ungue leonem, ex pede Herculem, vide ut supra, vultus ariete fortior, indication, symbolism, symbolization, semiology, semiotics, semeiology, semeiotics, Zeitgeist, characteristic, diagnostic, lineament, feature, trait, fingerprint, voiceprint, footprint, noseprint, cloven hoof, footfall, recognition (memory), diagnostic, divining rod, detector, sign, symbol, index, indice, indicator, point, pointer, exponent, note, token, symptom, dollar sign, dollar mark, type, figure, emblem, cipher, device, representation, epigraph, motto, posy, gesture, gesticulation, pantomime, wink, glance, leer, nod, shrug, beck, touch, nudge, dactylology, dactylonomy, freemasonry, telegraphy, chirology, byplay, dumb show, cue, hint, clue, clew, key, scent, signal, signal post, rocket, blue light, watch fire, watch tower, telegraph, semaphore, flagstaff, cresset, fiery cross, calumet, heliograph, guidon, headlight, mark, scratch, line, stroke, dash, score, stripe, streak, tick, dot, point, notch, nick, print, imprint, impress, impression, keyboard symbols, printing symbols, red letter, italics, sublineation, underlining, bold font, jotting, note, annotation, reference, blaze, cedilla, guillemets, hachure, quotation marks, ", double quotes, " ", parentheses, "( )", brackets, "", braces, "", left arrow, "<", right arrow, ">", forward slash, "/", backward slash, "\", exclamation point, "!", commercial at, "@", pound sign, "#", percent sign, "%", carat, "", ampersand, "&", asterisk, "*", hyphen, "-", dash, "-", "_", em dash, "--", plus sign, "+", equals sign, "=", question mark, "?", period, ", ", semicolon, ", ", colon, ":", comma, ", ", apostrophe, "'", single quote, "'", tilde, "~", badge, criterion, countercheck, countermark, countersign, counterfoil, duplicate, tally, label, ticket, billet, letter, counter, check, chip, chop, dib, totem, tessera, card, bill, witness, voucher, stamp, cacher, trade mark, Hall mark, signature, mark, autograph, autography, attestation, hand, hand writing, sign manual, cipher, seal, sigil, signet, hand and seal, paraph, brand, superscription, indorsement, endorsement, password, watchword, catchword, security card, pass, passkey, credentials, open sesame, timbrology, mot de passe, mot du guet, pass-parole, shibboleth, title, heading, docket, address card, visiting card, carte de visite, insignia, banner, banneret, bannerol, bandrol, flag, colors, streamer, standard, eagle, labarum, oriflamb, oriflamme, figurehead, ensign, pennon, pennant, pendant, burgee, blue Peter, jack, ancient, gonfalon, union jack, banderole, old glory, quarantine flag, vexillum, yellow-flag, yellow jack, tricolor, stars and stripes, bunting, heraldry, crest, coat of arms, arms, armorial bearings, hatchment, escutcheon, scutcheon, shield, supporters, livery, uniform, cockade, epaulet, chevron, garland, love knot, favor, beacon, cairn, post, staff, flagstaff, hand, pointer, vane, cock, weathercock, guidepost, handpost, fingerpost, directing post, signpost, pillars of Hercules, pharos, bale-fire, beacon-fire, l'etoile du Nord, landmark, seamark, lighthouse, balize, polestar, loadstar, lodestar, cynosure, guide, address, direction, name, sign, signboard, warning, omen, prefigurement, trace, record, warning &c, alarm, scepter, trophy, gauge, milestone, milepost, brand, fool's cap, check, telltale, test, mileage ticket, milliary, notification, advertisement, word of command, call, bugle call, trumpet call, bell, alarum, cry, battle cry, rallying cry, angelus, reveille, sacring bell, sanctus bell, exposition &c (explanation), proof, pattern, indicating, indicative, indicatory, denotative, connotative, diacritical, representative, typical, symbolic, pantomimic, pathognomonic, symptomatic, characteristic, demonstrative, diagnostic, exponential, emblematic, armorial, individual, known by, recognizable by, indicated, pointed, marked, denotable, indelible, in token of, symbolically, in dumb show, ecce signum, ex ungue leonem, ex pede Herculem, vide ut supra, vultus ariete fortior.

VB indicate, be the sign, of, denote, betoken, argue, testify, bear the impress, of, connote, connotate, represent, stand for, typify, symbolize, put an indication, put a mark, note, mark, stamp, earmark, blaze, label, ticket, docket, dot, spot, score, dash, trace, chalk, print, imprint, impress, engrave, stereotype, make a sign, signalize, underscore, give a signal, hang out a signal, beckon, nod, wink, glance, leer, nudge, shrug, tip the wink, gesticulate, raise the finger, hold up the finger, raise the hand, hold up the hand, saw the air, suit the action to the word, wave a banner, unfurl a banner, hoist a banner, hang out a banner, wave the hand, wave a kerchief, give the cue, show one's colors, give an alarm, sound an alarm, beat the drum, sound the trumpets, raise a cry, sign, seal, attest, underline, call attention to, give notice.

Record

VB record, put on record, place on record, chronicle, calendar, hand down to posterity, keep up the memory, commemorate, report, write, commit to writing, reduce to writing, put in writing, set down in writing, writing in black and white, put down, jot down, take down, write down, note down, set down, note, minute, put on paper, take note, make a note, take minute, take memorandum, make a return, mark, sign, enter, book, post, post up, insert, make an entry of, mark off, tick off, register, enroll, inscroll, file, burn into memory, carve in stone.

See related words and definitions of word "Sign" in Indonesian
Also see definition of "Sign" in Bible Study Dictionaries
copyright © 2012 Yayasan Lembaga SABDA (YLSA) | To report a problem/suggestion