Britney Spears has some words for Ozzy Osbourne after he crapped all over her free-spirited dance videos — and in the same breath … she’s sticking up for Kate Beckinsale.

The pop star went off on the Black Sabbath rocker Wednesday — not long after Ozzy aired out his opinion on BS’s habit of throwing up dance clips of herself at home … where she’s often twirling around and wearing hardly anything at all.

Britney starts out by defending Kate, writing … “I adore Kate Beckinsale especially because she’s from London. I realized how incredibly cruel people were talking about her IG saying she needs more age-appropriate content.”

She goes on to say that she appreciates Kate’s signature bow and how much she’s telling haters to piss off — and then pivots into how she herself has caught a lot of heat for her own videos … which some label weird/offputting.

Britney goes on to explain why she dances so much — she says she’s good at it, and loves it — and then takes a direct swipe at Ozzy and his family, adding … “I’m gonna do a photoshoot with Kate and tell the Osbourne family who is the most boring family known to mankind to kindly f*** off!!!”

Of course, she’s responding to Ozzy name-dropping Brit in a podcast he did with his brood — where he said he was fed up with Britney’s dance videos … calling them nauseating.