What is "universal algebra"

n. 1 (context uncountable English) A branch of mathematics dealing with equational classes of algebras, where similar theorems from disparate branches of algebra are unified. 2 (context countable English) An algebraic structure studied therein.

Universal algebra (sometimes called general algebra) is the field of mathematics that studies algebraic structures themselves, not examples ("models") of algebraic structures. For instance, rather than take particular groups as the object of study, in universal algebra one takes "the theory of groups" as an object of study.