bairn(chiefly Scottish), bambino, bud, chap(Southern & Midland), child, cub, juvenile, kid, kiddie(also kiddy), kiddo, moppet, sprat, sprout, squirt, whelp, youngling, youngster, youth

adolescent, minorkindergartner(also kindergartener), preschooler, rug rat(slang), schoolboy, schoolchild, schoolgirl, schoolkidbabe, baby, bantling, infant, neonate, nestling, newborn, toddler, tot, tyke(also tike), weanlingbrat, devil, hellion, imp, jackanapes, mischief, monkey, rapscallion, rascal, rogue, urchin, whippersnappercherubpreteen, preteen-ager, subteen, teen, teenager, teener, teenybopper, tweenlad, nipper, shaver, stripling, tadbobby-soxer, hoyden, tomboy