younker(n = noun.person) spring chicken, young person, youth - a young person (especially a young man or boy);

   A young person; a stripling; a yonker. [1913 Webster]

younker, n. archaic = YOUNGSTER.

Etymology:
MDu. jonckher f. jonc YOUNG + here lord: cf. JUNKER

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.