'conformance' originates from Medieval Latin/Old French via Latin-based formation: it combines the prefix 'con-' (from Latin meaning 'together' or 'with') and the root 'form' (from Latin 'forma', meaning 'shape' or 'form'), with the English noun-forming suffix '-ance'.

'conformance' developed from the verb 'conform', which came into English from Old French 'conformer' (itself from Latin 'conformare' 'to form together'). The noun was formed by adding the suffix '-ance' (from Old French/Latin '-antia') to express the state or quality of the verb.

Initially related to the idea of 'forming together' or 'having the same form'; over time the sense shifted toward 'complying with a standard or requirement', which is the dominant modern meaning.