Antonyms of adj full-grown

1 sense of full-grown

Sense 1
adult, big, full-grown, fully grown, grown, grownup -- ((of animals) fully developed; "an adult animal"; "a grown woman")

INDIRECT (VIA mature) -> immature -- (not yet mature)

Similarity of adj full-grown

1 sense of full-grown

Sense 1
adult, big, full-grown, fully grown, grown, grownup -- ((of animals) fully developed; "an adult animal"; "a grown woman")
       => mature (vs. immature) -- (having reached full natural growth or development; "a mature cell")