Englishlackadaisical
adjective
I was lackadaisical about my training:
careless, lazy, lax, unenthusiastic, halfhearted, uninterested, lukewarm, indifferent, uncaring, past caring, unconcerned, casual, offhand, blasé, insouciant, leisurely, relaxed;
apathetic, languid, languorous, lethargic, limp, listless, sluggish, enervated, spiritless, aimless, bloodless, torpid, passionless, idle, indolent, shiftless, inert, impassive, feeble;
informal laid back, couldn't-care-less, easy going, slaphappy;
British, vulgar slang half-arsed;
North American, vulgar slang half-assed;
rare Laodicean, pococurante.
▷antonyms enthusiastic, excited.