debonair

blithe, debonair, devil-may-care, gay, happy-go-lucky, insouciant, lighthearted, lightsome, slaphappy, unconcerned

blasé ( blase), breezy, cavalier, nonchalant; casual, easygoing, informal, laid-back, low-pressure, relaxed, unfussy

earnest, grave, serious, serious-minded, somber ( sombre); careful, cautious, heedful, wary; anxious, concerned, upset, worried; long-suffering, overburdened, sorrowful

debonair, smooth, sophisticated, svelte, urbane

cavalier, glib, slick, unctuous; civilized, couth, cultivated, cultured, genteel, graceful, gracious, poised, polished, refined, well-bred; cosmopolitan, metro, metropolitan, smart, worldly-wise; experienced, knowing, practiced ( practised), schooled, seasoned; amiable, appealing, attractive; assured, calm, collected, composed, confident, cool, placid, secure, self-assured, self-confident, self-possessed, serene, tranquil, undisturbed, unperturbed

awkward, clumsy, gauche, graceless, stiff, stilted, uncomfortable, uneasy, ungraceful, wooden; callow, green, inexperienced, puerile, raw; hick, parochial, provincial, rough-hewn, rustic ( rustical); inelegant, philistine, uncivilized, uncultured, unrefined; unsophisticated, unworldly; gawky, lubberly, stodgy, ungainly; diffident, insecure