1. quadral - Noun
2. quadral - Adjective
(grammar) A grammatical number referring to four (or more) things.
(mathematics) A set of points with all the combinatorial properties of a quadric (a quadric being the set of points of PG(n, q) whose coordinates satisfy a quadratic equation).
(rhetoric) A set of four phrases, separated by pauses when speaking or commas when writing.
A foursome.
(grammar) Referring to four (or more) things; of, in or relating to the quadral grammatical number.
(mathematics) Of or relating to quadral polynomials.
Source: en.wiktionary.org