THESAURUS
ail
ache, afflict, agonize, anguish, be affected with, be the matter, beset, bite, blanch, blench, bother, burn, chafe, complain of, complicate matters, concern, convulse, crucify, cut, discommode, distress, disturb, excruciate, feel ill, feel pain, feel the pangs, fester, fret, gall, give pain, gnaw, grate, grimace, grind, gripe, harass, harrow, have a misery, hurt, inconvenience, inflame, inflict pain, irk, irritate, kill by inches, labor under, lacerate, martyr, martyrize, nip, pain, perplex, perturb, pierce, pinch, plague, pother, pound, prick, prolong the agony, put out, put to it, put to torture, puzzle, rack, rankle, rasp, rub, shoot, shrink, smart, stab, sting, suffer, thrill, throb, tingle, torment, torture, trouble, try, tweak, twinge, twist, twitch, upset, vex, wince, worry, wound, wring, writhe
ROGET THESAURUS
ail
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.
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.