1. область, when used in an address, is abbreviated to обл.

2. Ukraine's administrative structure consists of 24 області (administrative regions), also the Autonomous Republic of Crimea, and two cities (Kyiv and Sevastopol) with special status; the principal city of each область is its administrative centre  

3. область in its figurative use means 'sphere, field, domain' (but домен is used for the Internet, physics, biology etc.)