A woman is suing Xavien Howard ... alleging the Miami Dolphins star knowingly gave her an "incurable STD."
The woman, ID'ed as "Jane Doe" in the suit, claims she met the football player back in 2018 ... and shortly afterward, began dating him. She says at the time, Howard told her he had no STDs -- and even provided her with a copy of his negative test results.
In 2019, however, she said in the suit that Howard discovered he had contracted genital herpes ... but never informed her of the diagnosis, and continued to have unprotected sex with her.