'babishly' originates from English, specifically the adjective 'babish' (formed from 'baby' + the suffix '-ish'), where 'baby' originally meant 'infant' and the suffix '-ish' meant 'having the quality of'.

'babish' (or older variant 'babyish') developed in English from the noun 'baby' plus the adjectival suffix '-ish'; the adverb 'babishly' was formed later by adding the suffix '-ly' to the adjective.

Initially it meant 'like a baby' (literally infant-like); over time it has been used more broadly to mean 'immature' or 'childish' in behavior or manner.