Definition of "contravariant"

(category theory, of a functor) which reverses composition  examples

(object-oriented programming) Using or relating to contravariance.  examples

(linear algebra, of a vector) Scaling inversely with a change of basis.  examples

(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.  examples