'neurodegenerative' is a compound formed from the combining form 'neuro-' (from Greek 'neûron' meaning 'nerve') and the adjective 'degenerative' (from Latin 'degenerare' via Old French/Latin medical usage), where 'neuro-' signified 'nerve' and 'degenerative' referred to 'decline or loss of function.'

'neuro-' originates from Greek 'neûron' and was later adopted into New Latin/medical formation as a combining form; 'degenerative' derives from Latin 'degenerare' ('de-' + 'genus') through Medieval/Scientific Latin and Old French into Middle English as 'degenerate' before becoming the adjective 'degenerative'. The modern English compound 'neurodegenerative' arose in 20th-century medical usage to describe diseases involving progressive neuronal loss.

Originally, 'degenerate' carried senses of 'falling away from an original kind or quality'; combined with 'neuro-' the modern term came to mean specifically 'involving progressive degeneration of nerve cells' in contemporary medical contexts.