unconcerned

1 having or showing freedom from worries or troubles playful and unconcerned despite his medical emergency Synonyms blithe, debonair, devil-may-care, gay, happy-go-lucky, insouciant, lighthearted, lightsome, slaphappy, carefreeRelated Words blasé (also blase), breezy, cavalier, nonchalant; casual, easygoing, informal, laid-back, low-pressure, relaxed, unfussyNear Antonyms earnest, grave, serious, serious-minded, somber (or sombre); careful, cautious, heedful, wary; anxious, concerned, upset, worried; long-suffering, overburdened, sorrowfulAntonyms careworn

2 having or showing a lack of interest or concern a featherbrain completely unconcerned about the important issues of the day Synonyms apathetic, casual, complacent, disinterested, incurious, insensible, insouciant, nonchalant, perfunctory, pococurante, indifferent, uncurious, uninterestedRelated Words halfhearted, lukewarm, tepid; aloof, cold, numb, remote, unemotional; callous, hard-hearted, insensitive, unfeeling; calm, cool, detached, dispassionate; careless, heedless, mindless; impassive, impervious, phlegmatic, stoic (or stoical), stolid; lethargic, listless; unimpressedNear Antonyms attentive, aware, conscientious, heedful, mindful; caring, sensitive, warmhearted; ardent, fervent, keen, passionate, warm, zealousAntonyms concerned, interested