'dehydrogenate' originates from Modern formation (English), specifically from the combination of the prefix 'de-' (from Latin) meaning 'remove' or 'reverse' and 'hydrogenate' (formed from 'hydrogen' + suffix '-ate').

'dehydrogenate' developed by prefixing 'de-' to 'hydrogenate'; 'hydrogenate' itself comes from 'hydrogen' (borrowed via French 'hydrogène' and New Latin 'hydrogenium'), where 'hydro-' comes from Greek 'hydōr' meaning 'water' and '-genes' meaning 'producing' or 'forming', and the chemical suffix '-ate' (from Latin/Greek formation practices) was added to form the verb.

Initially the elements 'hydro-' and '-genes' related to 'water-forming' (coined for the element hydrogen), and the full modern verb 'dehydrogenate' came to mean 'remove hydrogen' in chemical contexts; this meaning is a straightforward compositional development rather than a large semantic shift.