D defs.my
Entry 1 sense Webster, 1913

Impuberal

/(ĭm*pū"bẽr*al)/ · Im·pu·ber·al · IPA /ɪmˈpjuːbəɹəl/
01 a. Not having arrived at puberty; immature.
  1. 1.
    Not having arrived at puberty; immature.
    “In impuberal animals the cerebellum is, in proportion to the brain proper, greatly less than in adults.” Sir W. Hamilton.