Definition of: trinomial

(trī·nō′mē·əl) adjective
1. Biol. Of, having, or employing three terms or names
—the generic, the specific, and the subspecific or varietal, as Lynx rufus texensis, the Texas bobcat.
2. Math. Consisting of three terms connected by plus or minus signs or both.
—noun
1. An algebraic expression consisting of three terms connected by plus or minus signs or both, as 3x + y - 27z.
2. A trinomial name. Also tri·nom′i·nal (-nom′ə·nəl), tri·on′·y·mal (-on′ə·məl). [<TRI- + (BI)NOMIAL]