The stremma ( stremmata; , strémma) is unit of land area used mainly in Greece and Cyprus, equal to 1,000 square metres or approximately acre.
The ancient Greek equivalent was the square plethron, which served as the Greeks' form of the acre. It was originally defined as the area plowed by a team of oxen in a day but was nominally standardised as the area enclosed by a square 100 Greek feet (pous) to a side. It was the size of a Greek wrestling square.
The Byzantine or Morean stremma continued to vary depending on the period and the quality of the land, but usually enclosed an area between 900 and 1 900 m<sup>2</sup>. It was also originally known as a "plethron" but this was replaced during Byzantine times by the word "stremma", derived from the verb for "turning" the ground with a plough.
The Ottoman stremma or Turkish stremma, is the Greek (and occasionally English) name for the dunam, which is probably derived from the Byzantine unit. Again, this varied by region: some values include 1 270 m<sup>2</sup>, and 1 600 m<sup>2</sup>.