What's the "een" in Halloween?
isomorphic i·so·mor·phic (ī'sə-môr'fĭk)
Having a similar structure or appearance but being of different ancestry.
Related by an isomorphism.
Two mathematical objects are isomorphic if they have the same structure, i.e. if there is an isomorphism between them. For every component of one there is a corresponding component of the other.