Other forms: discriminants
A discriminant is a mathematical expression used to determine some properties of a larger equation or function. Outside of math, a discriminant is a property that distinguishes something from something else, or an adjective meaning "having good judgment."
In algebra, the discriminant is the part of the quadratic formula that is under the square root symbol. Plug in the numbers from a quadratic equation to determine how many and what type of roots (solutions) the equation has. More generally, a discriminant is any distinguishing attribute, as in "the discriminant between yellow and black labs is fur color." Adjectivally, a discriminant person is discerning: If your pals are always getting into trouble, perhaps you should be more discriminant when choosing friends.