THESAURUS
Languish
abate, ablate, bate, be eaten away, become suicidal, break, cave in, collapse, come apart, come unstuck, conk out, consume, consume away, corrode, crumble, decline, decrease, deliquesce, desiccate, despair, despond, deteriorate, die away, diminish, disintegrate, dive, droop, drop, drop off, dry up, dwindle, ebb, erode, fade, fade away, fail, faint, fall, fall away, fall off, fizzle out, flag, give out, give way, go downhill, go soft, go to pieces, hit rock bottom, hit the skids, lessen, let up, lose heart, lose strength, melt away, peak, peg out, peter out, pine, plumb the depths, plummet, plunge, poop out, reach the depths, run down, run low, sag, sear, shrink, shrivel, sink, subside, tail off, touch bottom, wane, waste, waste away, weaken, wear, wear away, wear thin, wilt, wither, wither away, wizen, yield
ROGET THESAURUS
Languish
Disease
VB
V, be ill, ail, suffer, labor under, be affected with, complain of, have, droop, flag, languish, halt, sicken, peak, pine, gasp, keep one's bed, feign sickness, lay by, lay up, take a disease, catch a disease, catch an infection, break out.
Decrease
VB
decrease, diminish, lessen, abridge, shrink, drop off, fall off, tail off, fall away, waste, wear, wane, ebb, decline, descend, subside, melt away, die away, retire into the shade, hide its diminished head, fall to a low ebb, run low, languish, decay, crumble, bate, abate, dequantitate, discount, depreciate, extenuate, lower, weaken, attenuate, fritter away, mitigate, dwarf, throw into the shade, reduce, shorten, subtract.
Inactivity
VB
be inactive, do nothing, move slowly, let the grass grow under one's feet, take one's time, dawdle, drawl, droil, lag, hang back, slouch, loll, lollop, lounge, poke, loaf, loiter, go to sleep over, sleep at one's post, ne battre que d'une aile, take it easy, take things as they come, lead an easy life, vegetate, swim with the stream, eat the bread of idleness, loll in the lap of luxury, loll in the lap of indolence, waste time, consume time, kill time, lose time, burn daylight, waste the precious hours, idle away time, trifle away time, fritter away time, fool away time, spend time in, take time in, peddle, piddle, potter, pudder, dabble, faddle fribble, fiddle-faddle, dally, dilly-dally, sleep, slumber, be asleep, hibernate, oversleep, sleep like a top, sleep like a log, sleep like a dormouse, sleep soundly, heavily, doze, drowze, snooze, nap, take a nap, dream, snore one's best, settle to sleep, go to sleep, go off to sleep, doze off, drop off, fall asleep, drop asleep, close the eyes, seal up the eyes, seal up eyelids, weigh down the eyelids, get sleep, nod, yawn, go to bed, turn, get some z's, stack z's, languish, expend itself, flag, hang fire, relax, render idle, sluggardize, mitigate.
Weakness
VB
be weak, drop, crumble, give way, totter, tremble, shake, halt, limp, fade, languish, decline, flag, fail, have one leg in the grave, render weak, weaken, enfeeble, debilitate, shake, deprive of strength, relax, enervate, eviscerate, unbrace, unnerve, cripple, unman, cramp, reduce, sprain, strain, blunt the edge of, dilute, impoverish, decimate, extenuate, reduce in strength, reduce the strength of, mettre de l'eau dans son vin.
Pain
VB
feel pain, suffer pain, experience pain, undergo pain, bear pain, endure pain, smart, ache, suffer, bleed, ail, be the victim of, labor under afflictions, bear the cross, quaff the bitter cup, have a bad time of it, fall on evil days, go hard with, come to grief, fall a sacrifice to, drain the cup of misery to the dregs, sup full of horrors, sit on thorns, be on pins and needles, wince, fret, chafe, worry oneself, be in a taking, fret and fume, take on, take to heart, cark, grieve, mourn, yearn, repine, pine, droop, languish, sink, give way, despair, break one's heart, weigh upon the heart.