A dunam, also known as a donum or dunum and as the old, Turkish, or Ottoman stremma, was the Ottoman unit of area equivalent to the Greek stremma or English acre, representing the amount of land that could be ploughed by a team of oxen in a day. Wikipedia

A unit of measurement of land area also spelled dunum Wikipedia Disambiguation

General topic for several units of area called dunam Wikidata

An Ottoman Turkish unit of surface area nominally equal to 1,600 square (Turkish) paces but actually varied at a provincial and local level according to land quality to accommodate its colloquial sense of the amount of land able to be plowed in a day, roughly equivalent to the Byzantine stremma or English acre. Wiktionary