Telecommunication Regulatory Authority, an independent organization established in the United Arab Emirates in 2003 to oversee the telecommunications sector in the country.

Telecommunications Act of 1996, or the Telecom Reform Act, a significant overhaul of United States telecommunications policy.

Theodore Roosevelt Association, an organization chartered by Act of Congress in 1920 dedicated to President Theodore Roosevelt.

Theory of reasoned action, a psychological theory created by Martin Fishbein and Icek Ajzen

Taiwan Railway Administration (台灣鐵路管理局), the government agency responsible for managing passenger and freight service on conventional rail in Taiwan.

Traumatic rupture of the thoracic aorta, another name for traumatic aortic rupture.

Taiwan Relations Act, an act of the United States Congress passed in 1979 after the establishment of relations with the People's Republic of China and the breaking of relations between the United States and the Republic of China on Taiwan by President Jimmy Carter.

TRA is a three-letter abbreviation that can refer to:

Tomb Raider: Anniversary, the next game in the Tomb Raider series and a 2007 remake of the original Tomb Raider.