contravariant

contravariant (not comparable)

1. (category theory, of a functor) Which reverses the order of morphism composition: formally, which associates each morphism ${\displaystyle f:X\to Y}$ to a morphism ${\displaystyle F(f):F(Y)\to F(X)}$.

   Antonym: covariant

2. (object-oriented programming) Using or relating to contravariance.
3. (linear algebra, of a vector) Scaling inversely with a change of basis.

• contravector

contravariant (plural contravariants)

1. (algebra) A bihomogeneous polynomial in dual variables of x, y, ... and the coefficients of some homogeneous form in x, y, ... that is invariant under some group of linear transformations.