The arpent was a French term, normally used to indicate the extent of vineyards in Domesday Book. Of the 26 occurrences of the word in Great Domesday, 21 apply to vineyards, the remaining five - all in Wiltshire - to meadow or woodland. Vines are only occasionally measured in acres. There are no contemporary indications of the area of the arpent, or of its relationship to other units; at a later date, it was a square measure of rather more than half an acre.
For more detail, see R.R. Darlington, 'Introduction to the Wiltshire Domesday', Victoria History of the county of Wiltshire, vol. 2, edited by R.B. Pugh and E. Crittall (1955), pages 42-177; and Philip Grierson, 'Weights and measures', Domesday Book: studies, edited by Ann Williams and R.W.H. Erskine (1987), pages 80-85.