man-child

from WordNet (r) 3.0 (2006)

man-child
    n 1: a child who is male [syn: {male offspring}, {man-child}]
         [ant: {female offspring}]

from Moby Thesaurus II by Grady Ward, 1.0

23 Moby Thesaurus words for "manchild":
      boy, bub, bubba, buck, bud, buddy, colt, cub, fellow, fledgling,
      hobbledehoy, lad, laddie, master, muchacho, pup, puppy, schoolboy,
      sonny, sonny boy, whelp, young man, youth