PCA

1. abbreviationhuman sciencesAbbreviation of Proto-Central Algonquian.
2. USabbreviationlawAbbreviation of Posse Comitatus Act, the U.S. law called "Posse Comitatus Act", 20 Stat. 152 aka 18 U.S.C. § 1385.
3. USabbreviationhistoricalinitialismgovernmentInitialism of Progressive Citizens of America.

   The PCA was demonstrably a Communist-front organization, and most of the Hollywoodites whom it rallied to its support were members of the Communist Party, some of them having been notorious as such for many years.

   1956, United States. Congress. House. Committee on Un-American Activities, Hearings, page 171

plural PCAs

1. abbreviationaeronauticsAbbreviation of propulsion controlled aircraft (system/unit), an aircraft with a control system with two or more engines arrayed abreast, allowing descent, ascent, turns by adjusting the throttle control to the engines (sometimes used attributively).
2. abbreviationmathematicsAbbreviation of principal components analysis.
3. abbreviationmedicineAbbreviation of patient-controlled analgesia; palliator.
4. abbreviationinitialismanatomyInitialism of posterior cerebral artery.
5. abbreviationinitialismbusinessInitialism of printed circuit assembly.

   Synonyms: PCBA