'phosphorylate' originates from scientific New Latin/chemistry coinage built from 'phosphoryl' + the chemical suffix '-ate'; 'phosphoryl' ultimately comes from Greek 'phosphoros' meaning 'light-bearing' (via Latin/French 'phosphate').

'phosphorylate' was formed in the 19th century from the name of the radical 'phosphoryl' (itself from 'phosphate') plus '-ate' to indicate a derivative or salt, and it entered modern English usage through scientific literature.

Initially it named the chemical process of forming a phosphoryl derivative or salt; over time it has come to mean more specifically the enzymatic or chemical addition of a phosphate group to a molecule in biochemistry.