1.AdjectiveBoth left equivalent and right equivalent; Having the property that there exists a pair of mappings M1 (A->B) and M2 (B->A) such that M1M2(A) is equivalent to applying the unity operator to A and M2 M1(B) is equivalent to applying the unity operator to B.
2.AdjectiveCapable of replacing a bond formed by H2 to any molecule.