bastardise

verb3

1. •
   To claim or demonstrate that someone is a bastard, or illegitimate.

   • Our law is so indulgent as not to bastardize the child, if it be born, though not begotten, in lawful wedlock. — 1765
2. •
   To reduce from a higher to a lower state, such as by removing refined elements or introducing debased elements; to debase.

   • The simplified word processor is a less-functional, bastardized version of the full program.
3. •
   To beget out of wedlock.

   • I should / have been that I am, had the maidenliest star in the / firmament twinkled on my bastardizing. — 1603