See lethargic in Webster's New World Roget's A-Z Thesaurus II
adjective
Lacking mental and physical alertness and activity:
hebetudinous, sluggish, stupid, stuporous, torpid. (Slang) dopey. See actionWithout emotion or interest:
apathetic, detached, impassive, incurious, indifferent, insensible, listless, phlegmatic, stolid, unconcerned, uninterested, unresponsive. See feelings
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