'self-abnegation' is formed in Modern English from the prefix 'self-' (meaning 'oneself') plus 'abnegation'. 'abnegation' originates from Latin 'abnegatio', from 'abnegare' meaning 'to refuse' ('ab-' meaning 'away' and 'negare' meaning 'to deny').

'abnegation' came into English via Latin 'abnegatio' and Old French forms, appearing in Middle English as 'abnegacion' or similar, and later combining with the native English element 'self-' to create 'self-abnegation'.

Initially, 'abnegation' meant 'the act of refusing or denying' in a general sense; over time, in the compound 'self-abnegation' it came to denote specifically the denial or renunciation of oneself (self-denial or self-sacrifice).