CM first responded to an X post from the Irish Independent newspaper about the outcome of his case, which included the line, "Justice has been served."

The MMA star replied, "Justice was served for James Lawrence, yes! Deplorable what they done. Nikita hand, vicious liar! APPEAL!"

James Lawrence, who Conor referenced, was also being accused of sexual assault ... but the civil jury did not find him liable.

It was after that initial X post that Conor really went off ... going scorched earth in a lengthy social media rant.

Said CM ... "Two men falsely accused. One vindicated, the other soon to be! Congrats James Lawrence on absolute exoneration! Twice this heinous accusation was put to you and twice it was shown as FALSE! LIES!"

Conor went on ... "It is absolutely disgraceful what they put you through here. Disgraceful! I look forward to seeing you further vindicate yourself and lambast those responsible in court! We know what happened that night! Everyone present knows, yet it was ignored. Every single statement of persons present on the night was ignored."

He ended with, "On we fight! Justice and truth will prevail! Appeal! Appeal! Appeal! As well as other. Congrats James! Onwards and upwards! 🙏"

As TMZ reported ... a jury found Conor liable for assault in his civil rape case that had been going on all month long -- after Nikita Ni Lamhain claimed McGregor and another man had sex with her against her will after a 2018 Christmas party.

CM and James adamantly denied the allegations ... with the 36-year-old fighter claiming their encounter was entirely consensual.

Jurors in the case clearly didn't believe Conor's side ... and awarded Ni Lamhain roughly $250,000 in damages. In their ruling, they did state they found that James did NOT assault the woman.