'arpent' originates from Old French, specifically the word 'arpent', where the root is associated with early Germanic/Frankish measuring terms (related to ropes or rods used for measurement).

'arpent' changed from Old French 'arpent' (and Medieval Latin forms such as 'arpentum') and was borrowed into English with the same form; it remained as a regional measure, especially in French-speaking North America.

Initially, it referred generally to a measure (length or area) used locally; over time it became established mainly as a unit of land area (with regionally varying exact values).