An Etymological Dictionary of Astronomy and Astrophysics

An agent or factor that determines the nature of something or that fixes or conditions an outcome.
Math.: An algebraic expression used in the solution of systems of linear equations, which consists of the sum of products of elements, each with an appropriate algebraic sign, usually written in a square array.

Etymology (EN): From → determine + -ant suffix forming noun.

Etymology (PE): Âtarmgar, from âtarm present stem of âtarmidan→ determine + -gar, → detector.