Misspelling of je ne sais quoi.

plural of quadrille paper

A surname.

The 99th sura (chapter) of the Qur'an.

plural of quadratic form

(mathematics, number theory, algebra) A homogeneous polynomial of degree 2 in a given number of variables.

plural of quadratic residue

(number theory, modular arithmetic) For given positive integer n, any integer that is congruent to some square m² modulo n.

An edible clam native to the North Atlantic Ocean, Arctica islandica

(rare) A situation in which three people vie for the love of a fourth person.