'developmentally' originates from English, specifically the word 'developmental', where the root 'development' comes from 'develop' + the adjectival suffix '-al' meaning 'relating to', and the adverbial suffix '-ly' meaning 'in a ... manner'.

'developmentally' changed from the adjective 'developmental', which was formed from the noun 'development' (modern English). 'Development' comes from Middle English 'developen' (to unwrap, unfold) and Old French 'desveloper' (to unwrap), and earlier roots meaning 'to wrap/unwrap', eventually giving the sense of 'bring to light, unfold, grow' in modern English.

Initially the root sense was 'to unwrap' or 'to unfold', but over time it evolved to mean 'to bring into a fuller state or progress' and now 'developmentally' means 'in terms of development or growth'.