1. (superl.) Deficient in physical strength; weak; infirm; debilitated.

2. (superl.) Wanting force, vigor, or efficiency in action or expression; not full, loud, bright, strong, rapid, etc.; faint; as, a feeble color; feeble motion.

3. (v. t.) To make feeble; to enfeeble.

abulic afraid aged ailing anemic anile asthenic backward barely audible blear bleared bleary bloodless blurred blurry cachectic chicken confused cowardly crabbed dark debilitated decrepit decrescendo delicate dim dim-witted distant dizzy doddered doddering doddery drained drooping droopy dull effete emasculated enervated enfeebled etiolated exhausted failing faint faint-voiced fainthearted faintish feckless feebleminded filmy flabby flaccid flimsy floppy foggy forceless fossilized fragile frail fuzzy gentle gerontal gerontic gone gutless half-baked half-heard half-seen half-visible half-witted hazy healthless helpless ill-defined imbecile imperceptible impotent impuissant in poor health inadequate inconclusive inconspicuous indefinite indistinct indistinguishable ineffective ineffectual infirm insignificant insubstantial insufficient invalid invertebrate lame languid languishing languorous limber limp listless low low-profile lustless marrowless merely glimpsed misty moribund moronic mossbacked moth-eaten mummylike murmured namby-pamby nerveless obscure out of focus pale palsied paltry papery-skinned peaked peaky pianissimo piano pithless pliable pooped poor powerless puny ravaged with age reduced reduced in health rickety rubbery run to seed run-down rusty sapless scarcely heard semivisible senile shadowy shaky shoddy shriveled sickly simpleminded sinewless slack slight slow slow-witted soft soft-sounding soft-voiced spineless spiritless strengthless stricken in years subaudible subdued thin timeworn tottering tottery unavailing uncertain unclear unconvincing undefined unhardened unhealthy unmanned unnerved unplain unproved unrecognizable unrigorous unsatisfactory unsound unstrung unsubstantial unsustained vague valetudinarian valetudinary weak weak-kneed weak-minded weak-voiced weak-willed weakened weakly wet whispered wishy-washy with low resistance withered wizened woozy