Udar may refer to:

• Udar, a village in East Azerbaijan Province, Iran
• Udar revolver, an experimental Russian revolver
• UDAR, Ukrainian political party Ukrainian Democratic Alliance for Reform

Abdar (, also Romanized as Abdar; also known as Udar) is a village in Sahandabad Rural District, Tekmeh Dash District, Bostanabad County, East Azerbaijan Province, Iran. At the 2006 census, its population was 68, in 13 families.

The Ukrainian Democratic Alliance for Reform (; the acronym UDAR/УДАР translates to "strike" or "punch", ) was a political party in Ukraine headed by retired Ukrainian professional heavyweight boxer and the WBC world heavyweight champion emeritus Vitali Klitschko. It merged into the Petro Poroshenko Bloc on 28 August 2015.