bastardize

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.

The case of a king who falsely charges his wife with adultery, seeks to execute her, and bastardizes his daughter resonates strongly with the plot of The Winter's Tale, and in fact suggests a reading of the play as an allegory of Anne's downfall and Elizabeth's bastardization, seventy-five years after the fact.

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.

2017, Douglas Charles Kane, Beren and Lúthien (2017) by J.R.R. Tolkien, edited by Christopher Tolkien, in Journal of Tolkien Research, Volume 4, Issue 2, Article 5, The third potential audience is the general public at large, who either never has read any of Tolkien’s books or perhaps read The Lord of the Rings and/or The Hobbit long ago, but whose knowledge about Tolkien’s created secondary universe comes, if at all, mostly from seeing Peter Jackson’s bastardized adaptations of The Lord of the Rings and/or The Hobbit.

To beget out of wedlock.

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