mongrelize

verb (used with object), mon·grel·ized, mon·grel·iz·ing.

1. to subject (a breed, group, etc.) to crossbreeding, especially with one considered inferior.
2. to mix the kinds, classes, types, characters, or sources of origin of (people, animals, or things).
3. to make debased or impure: The French they speak is mongrelized.

verb

1. (tr) to make mixed or mongrel in breed, race, character, kind, etc