THESAURUS
boyish
adolescent, airy, attenuate, attenuated, beardless, boylike, calflike, childish, childlike, coltish, delicate, diaphanous, diluted, ethereal, fine, fine-drawn, finespun, flimsy, frail, gauzy, girlish, girllike, gossamer, gracile, immature, insubstantial, juvenile, kiddish, lacy, light, maiden, maidenly, misty, papery, puerile, puplike, puppyish, puppylike, rare, rarefied, slender, slenderish, slight, slight-made, slim, slimmish, slinky, small, subtle, svelte, sylphlike, tenuous, thin, thin-bodied, thin-set, thin-spun, thinnish, threadlike, vague, wasp-waisted, watered, watered-down, watery, weak, willowy, wiredrawn, wispy, young, youthful
ROGET THESAURUS
boyish
Infant
N
infant, babe, baby, babe in arms, nurseling, suckling, yearling, weanling, papoose, bambino, kid, vagitus, child, bairn, little one, brat, chit, pickaninny, urchin, bantling, bratling, elf, youth, boy, lad, stripling, youngster, youngun, younker, callant, whipster, whippersnapper, whiffet, schoolboy, hobbledehoy, hopeful, cadet, minor, master, scion, sap, seedling, tendril, olive branch, nestling, chicken, larva, chrysalis, tadpole, whelp, cub, pullet, fry, callow, codlin, codling, foetus, calf, colt, pup, foal, kitten, lamb, lambkin, aurelia, caterpillar, cocoon, nymph, nympha, orphan, pupa, staddle, girl, lass, lassie, wench, miss, damsel, demoiselle, maid, maiden, virgin, hoyden, infantine, infantile, puerile,
boyish, girlish, childish, babyish, kittenish, baby, newborn, unfledged, new-fledged, callow, in the cradle, in swaddling clothes, in long clothes, in arms, in leading strings, at the breast, in one's teens.