Gilbert Arenas Sues Laura Govan for Repeating STD Claim

Gilbert Arenas is gunning for his ex-wife in court for repeating an STD claim about him that already cost her $110k ... TMZ has learned.

The ex-NBA star filed a defamation lawsuit against Laura Govan, as well as her attorney, Maya Shulman, over a December blog post about the longstanding war between the exes. In the post, Shulman said Laura was "stating a fact" when she accused Gilbert of giving her an STD.

As we reported, Gilbert won a hefty defamation judgement against Laura over that very allegation. In the new suit, he says Laura and her attorney clearly didn't learn their lesson -- and the December comment constitutes another instance of smearing his good name.

He says Shulman dug her own grave when she issued a retraction -- in the comments section of the blog -- admitting she doesn't "know any 'fact' that supports" Laura's STD claims. Gilbert says it proves she knowingly made a false statement.

He adds the retraction didn't come until 2 weeks later, and was NOT prominent on the site. He's suing both women for damages.