Bastardize

Part of speech: verb (v.)

1. To make or prove to be a bastard; to stigmatize as a bastard; to declare or decide legally to be illegitimate. The law is so indulgent as not to bastardize the child, if born, though not begotten, in lawful wedlock. Blackstone.

2. To beget out of wedlock. [R.] Shak.