50 Cent is ripping into Conor McGregor for calling him a bitch in Thursday's press conference ... mocking the UFC superstar for getting choked out by Nate Diaz.
ICYMI -- 50 called out Conor for using his famous "Floyd can't read" insult (which Fitty used when he was beefin' with Floyd a few years back) in Toronto ... saying T.B.E.'s "gonna kill him for saying that."
Conor responded to the N.Y. rapper's comments during the Brooklyn stop of the world tour Thursday ... simply saying "50 Cent's a bitch!"
Fitty didn't take it lightly, calling out the Notorious .