'ancress' originates from Middle English, specifically the word 'ancre', which was the feminine form of 'anchorite', from Old English 'ancor', from Medieval Latin 'anchoreta', from Greek 'anachōrētēs', where 'ana-' meant 'back' and 'chōrein' meant 'to withdraw'.

'ancre' (Middle English) was used for a female religious recluse, and eventually became the modern English word 'ancress'.

Initially, it meant 'female religious recluse', and this meaning has remained largely unchanged in modern usage.