Definitions
1.NounA set of two elements treated as one; a pair.
2.NounTwo persons in an ongoing relationship; a dyadic relationship.
3.NounThe relationship or interaction itself in reference to a couple.
4.NounAny set of two different pitch classes.
5.NounAn element, atom, or radical having a valence of or combining power of two.
6.NounA chromosome structure, usually X- or V-shaped, consisting of two condensed sister chromatids joined by a centromere.
7.NounA secondary unit of organisation consisting of an aggregate of monads.
8.NounA tensor of order two and rank one.