- a region in E Greece: a former division of ancient Greece. 5208 sq. mi. (14,490 sq. km).
- a region of E Central Greece, on the Aegean: an extensive fertile plain, edged with mountains. Pop: 609 100 (2001). Area: 14 037 sq km (5418 sq miles)Modern Greek name: Thessalía (ˌθɛsaˈljia)