(astronomy) A stellar system in which two stars orbit around their center of mass; double star.

(arithmetic) arithmetic using binary numbers

(mathematics, computer science) A data structure in which each node has at most two children, each node but the root has one parent, and there are no cycles.

(biology) The process whereby a cell divides asexually to produce two daughter cells.

(mathematics) a function of the type f:V⨯V→V, or more generally, a function of the type f:U_1⨯U_2⨯...⨯U_n→V in which exactly two of the sets Uᵢ are equal to V.

(astronomy) A pair of quasars which gravitationally interact with each other, unlike a standard double quasar, which does not interact.

A gender system in which people are categorized, in terms of gender and often also sex, exclusively as either male or female.

plural of binary quasar

plural of binary operation

plural of binary function