Ronda Rousey: REMATCH WILL HAPPEN ... I'm Not Retiring

Ronda Rousey is calling BS on rumors she's done in the UFC -- telling TMZ Sports a rematch with Holly Holm will DEFINITELY happen in 2016.

There have been rumblings that Rousey could leave the octagon for good to focus on her blossoming career in Hollywood ... especially now that she just inked a new movie deal with Tina Fey.

But over the weekend, Rousey couldn't have been more clear -- she wants another crack at Holly ... and she's working with Dana White to figure out a date pronto.