hermicity

Noun

 * 1) The quality that an operator has of being Hermitian.
 * Unitarity is to hermicity what orthogonality is to symmetry. (That is, conjugation by unitary matrices preserves a Hermitian matrix&rsquo;s hermicity, just as conjugation by orthogonal matrices preserves a symmetric matrix&rsquo;s symmetry: $$(OSO^{-1})^T = (OSO^T)^T = O^{TT} S^T O^T = O S O^T = OSO^{-1}$$; $$ (UHU^{-1})^\dagger = (UHU^\dagger)^\dagger = U^{\dagger \dagger} H^\dagger U^\dagger = UHU^\dagger = UHU^{-1}$$.