Lethargic

a.

1.

Pertaining to, affected with, or resembling, lethargy; morbidly drowsy; dull; heavy.

Adj.

1.

lethargic - deficient in alertness or activity; "bullfrogs became lethargic with the first cold nights" Synonyms: unergetic Antonyms: energetic - possessing or exerting or displaying energy; "an energetic fund raiser for the college"; "an energetic group of hikers"

Laodicean, Olympian, aloof, anesthetized, apathetic, benumbed, blah, blase, bored, cataleptic, comatose, dead, debilitated, desensitized, detached, dilatory, disinterested, doped, dopey, dormant, dozy, dreamy, droopy, drowsy, drugged, drugged with sleep, dull, enervated, exanimate, exhausted, fagged out, faineant, fatigued, half asleep, heartless, heavy, heavy with sleep, heavy-eyed, hebetudinous, hopeless, idle, impassive, in a stupor, inactive, inanimate, indifferent, indolent, inert, insouciant, jaded, lackadaisical, laggard, languid, languorous, lazy, leaden, lifeless, lumpish, moribund, napping, narcoleptic, narcose, narcotized, narcous, nodding, nonchalant, numb, numbed, oscitant, out of it, passive, pluckless, pooped, resigned, sated, sedated, slack, sleep-drowned, sleep-drunk, sleep-filled, sleep-swollen, sleepful, sleepy, slothful, slumberous, slumbery, snoozy, somnolent, soporific, spiritless, spunkless, stagnant, stagnating, stoic, stolid, stretchy, stultified, stupefied, stupid, stuporose, stuporous, supine, tired, torpid, uncaring, unconcerned, uninterested, vegetable, vegetative, wan, weak, weary, withdrawn, world-weary, yawning, yawny