The pop star posted a lengthy social media rant Tuesday, addressing the jokes that were flying online during the Grammys, when she introduced Kim Petras and Sam Smith before they performed their Grammy-winning song "Unholy."

Madonna says the folks judging her physical appearance are focusing on the wrong thing -- Kim was the first trans woman to perform at the Grammys -- and she says the photos were "taken with a long lens camera by a press photographer that would distort anyone's face!!"

She says it's just the latest example of her being "caught in the glare of ageism and misogyny that permeates the world we live in."

64-year-old Madonna says anyone making wisecracks are part of a bigger problem ... she says our society refuses to celebrate women over the age of 45 and feels the need to punish women who, like her, are strong-willed, hard-working and adventurous.

Madonna's really digging in her heels ... saying she's never apologized for the way she looks or dresses and she sure as heck isn't going to start now.

While it was mostly Twitter users hurling insults, Madonna adds ... "I have been degraded by the media since the beginning of my career but I understand that this is all a test and I am happy to do the trailblazing so that all the women behind me can have an easier time in the years to come."

Madonna's also channeling another big winner from the Grammys, saying ... "In the words of Beyoncé 'You won't break my soul.'"

Don't expect Madonna to shy away from the cameras, long lenses or otherwise ... she says she looks forward to many more years of subversive behavior, pushing boundaries, standing up to the patriarchy and enjoying her life.