'topically' originates ultimately from Greek, specifically the word 'topos', where 'topos' meant 'place'. The adjective 'topical' was formed via Latin/Medieval Latin and English, and the adverb 'topically' derives from that adjective.

'topically' changed from English adjective 'topical' (from Late Latin 'topicus' and Greek 'topikos', from 'topos'), and the adverbial suffix '-ly' was added in English to form 'topically'.

Initially connected to the idea of 'place' (from Greek 'topos' meaning 'place'); over time it came to mean both 'relating to a subject or topic' and 'applied to a particular place (e.g., on the skin)' in modern usage.