TCA may refer to:
Chemistry and biochemistry
- Toxin complex a, an insecticidal toxin complex produced by Photorhabdus luminescens bacteria
- Tricarboxylic acid cycle, an alternate name for the citric acid cycle pathway in cellular metabolism
- Trichloroacetic acid, chemical used to precipitate protein in serum
- 2,4,6-Trichloroanisole, cause of cork taint in wine
- Tricyclic antidepressant, a class of medications
- TCA, a codon for the amino acid serine
Culture and media
- Taiwanese Cultural Association
- Tekeyan Armenian Cultural Association, a network of Armenian cultural organisations
- Television Critics Association
- The Canadian Amateur, radio amateur magazine
- Tribune Content Agency, a syndication company owned by Tribune Publishing
- Triple Crown of Acting is a term used in the American entertainment industry to describe actors who have won a competitive Academy Award, Emmy Award, and Tony Award in the acting categories
- Twentieth Century Animation, the animation division of 20th Century Studios
Economics and finance
Education
- The Classical Academy (Colorado), Colorado Springs, US
- Trinity Christian Academy (Deltona, Florida), US
- Trinity Christian Academy (Jackson, Tennessee), US
Organizations
- Taipei Computer Association
- The Consulting Association
- Total Community Action
- Trans-Canada Air Lines, predecessor to Air Canada
- Train Collectors Association
- Transportes Carga Aérea, a defunct Brazilian airline
Politics
- Taiwan Constitution Association, a political party in Taiwan
- EU–UK Trade and Cooperation Agreement, between the UK and the EU (2020)
- The Competition Authority (Ireland) (2002–2014)
Other uses
- Terminal control area, a volume of controlled airspace
- Topology change acknowledgement, a message in the 802.1D Spanning Tree Protocol (STP)
- Transportation Corridor Agencies, a toll road authority in Orange County, California
- Traumatic cardiac arrest, due to trauma
- Tennant Creek Airport, IATA airport code "TCA"
- Turks and Caicos Islands, country code
- Tropical Cyclone Advisory, tropical forecast service for international aviation safety