Pertaining to, or characterized by, descent from more than one root form, or from many different root forms; polygenetic; -- opposed to monophyletic.

Term applied to a group of organisms which does not include the most recent common ancestor of those organisms; the ancestor does not possess the character shared by members of the group.

A group of taxa that are derived from two or more ancestral forms not common to all members, (opposite of monophyletic).

A taxon whose members are derived from two or more separate and different ancestral lineages. This is often the result of convergent evolution.