The stremma (pl. stremmata; Greek: στρέμμα, strémma) is unit of land area used mainly in Greece and Cyprus, equal to 1,000 square metres or approximately ¼ 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^[1] but was nominally standardized 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 900–1,900 m² (9,700–20,500 sq ft).^[2] It was originally also known as the "plethron" but this was eventually replaced by "stremma", derived from the verb for "turning" the ground with a Byzantine plow.^[3]

The Ottoman stremma, often called the Turkish stremma, is the Greek (and occasionally English) name for the dunam, which in turn is probably derived from the Byzantine unit.^[4] Again, this varied by region: some values include 1,270 m² (13,700 sq ft),^[5] and 1,600 m².^[6]

One modern stremma is equivalent to:

• 1 E3 m² for further comparisons
• Byzantine units
• Conversion of units
• Greek units
• Metric units