Kesha has penned a lengthy tirade taking aim at a critic who bodyshamed her online.

The 29-year-old singer has been honest about her battles with eating disorders and depression in the past, and she spent time in rehab back in 2014 to battle her body image demons.

And, after an online troll criticized her figure and looks on Instagram, the star called out his negative opinions in a powerful post on the social media site.

"Dear @jackknife76. I see that you would very much like me to know that you think I'm ugly, and also a 'whore'," she wrote. "Well, I understand that that is your opinion, but I disagree. I'm not perfect but I'm pretty f**king magical. and also, I am not, in fact, a whore."

"Also bullying someone who has struggled publicly with body issues is pretty mean," she continued. "Thank god I'm in a place in my life where I feel empowered to address your nasty comments instead of letting them destroy me.

"On behalf of anyone anywhere who struggles with body image, STOP IT. my body is not your business. In conclusion, kiss my magical imperfect a**!"

The empowering note was posted alongside a photo of the singer wearing a swimsuit on a beach, bending over to show her backside.

This isn't the first time the TiK ToK hitmaker has slammed online bodyshamers. In May (16), she posted a snap of herself raising her middle fingers to the sky, and captioned it with a defiant message to her online haters.

"I have been battling depression and an eating disorder for a while now," she wrote. "My career is in a strange place and it feels like I'm fighting an uphill fight some days. But I have decided to take my life back. My freedom. MyDr Lukehappiness. My voice. My worth. I will not just f***ing be quiet and hide. Today I will say f**k it and live."

Kesha is currently embroiled in an ongoing legal battle with her former mentor and music producer Dr Luke, real name Lukasz Gottwald, who she has accused of sexual, physical, and emotional abuse. The producer has denied the allegations.