Characteristic of a baby.

Befitting or characteristic of a young boy; SYN. boylike, schoolboyish.

ETYM Latin jejunus fasting, hungry, dry, barren, scanty; of unknown origin.
1. Lacking matter; empty; void of substance.
2. Puerile, immature.
3. Lacking interest or significance; dull or insipid; dry; empty.
4. Empty; sterile; dry; naive; immature.

ETYM Latin puerilis, from puer a child, a boy: cf. French puéril.
Of or characteristic of a child; childish.