Covariance and contravariance may refer to: Covariance and contravariance of vectors, in mathematics and theoretical physics Covariance and contravariance of functors, in category theory Covariance and contravariance (computer science), whether a type system preserves the ordering ≤ of types An informal synonym for invariance (physics)
See also Covariance, in probability theory and statistics, the measure of how much two random variables vary together Covariance (disambiguation)