In abstract algebra, an orthomorphism is a certain kind of mapping from a group into itself. Let G be a group, and let ø be a permutation of G. Then ø is an orthomorphism of G if the mapping f defined by f(x) = x<sup>âÂÂ1</sup> ø(x) is also a permutation of G. A permutation àof G is a complete mapping if the mapping g defined by g(x) = xÃÂ(x) is also a permutation of G. Orthomorphisms and complete mappings are closely related.