'antre' originates from Old French, specifically the word 'antre', where the Latin root 'antrum' meant 'cave'.

'antre' changed from the Latin word 'antrum' into Old French 'antre' and was adopted into Middle English as 'antre', eventually surviving in modern English as the rare/poetic word 'antre'.

Initially it meant 'cave' in Latin and Old French; over time the basic meaning has remained but usage narrowed to literary or archaic contexts in modern English.