lactase

affable, breezy, devil-may-care, easygoing, happy-go-lucky, laid-back, loosey-goosey, mellow

carefree, nonchalant, unconcerned

assured, confident, self-assured

aloof, detached, dispassionate, indifferent

bovine, impassive, phlegmatic, sober, stolid

relaxed, relieved, tranquilized (also affable, breezy, devil-may-care, easygoing, happy-go-lucky, laid-back, loosey-goosey, mellow

carefree, nonchalant, unconcerned

assured, confident, self-assured

aloof, detached, dispassionate, indifferent

bovine, impassive, phlegmatic, sober, stolid

relaxed, relieved, tranquilized (also