Antonyms of adj babyish

1 sense of babyish

Sense 1
babyish -- (characteristic of a baby; "babyish tears and petulance")

INDIRECT (VIA immature) -> mature -- (characteristic of maturity; "mature for her age")

Similarity of adj babyish

1 sense of babyish

Sense 1
babyish -- (characteristic of a baby; "babyish tears and petulance")
       => immature (vs. mature) -- (characteristic of a lack of maturity; "immature behavior")