Quenya: Angelic Powers, sing.: Vala
The 14 most powerful Ainur, who entered the world, Eä, hence they are also called the Powers of the World.
The 7 Lords of the Valar are :
Manwë, Ulmo, Aulë, Oromë, Mandos, Lórien, Tulkas,
and the 7 Valier, the Queens of the Valar:
Varda, Yavanna, Nienna, Estë, Vairë, Vána, and Nessa.
Also called the Powers and Lords of the West
Tolkien himself did not use the term Valar consistently, sometimes he used it for all the Ainur that entered the world, but usually the term was referring to the "mightiest" of them, the lesser ones are called Maiar.
See also: Ainur, Maiar, Aratar