The 'Shake It Off' star told Rolling Stone that she penned the angry track in response to a female artist that "did something so horrible" to her involving sabotaging Taylor's arena tour.
Taylor, 24, said that for years she wasn't sure if she and the unnamed popstar were friends or not as the other artist would say things to her that could be construed as friendly or jibes.
"She would come up to me at awards shows and say something and walk away, and I would think, 'Are we friends, or did she just give me the harshest insult of my life?'"
Taylor said she realised the truth last year when this popstar apparently tried to wreck plans for her arena tour by hiring staff that Taylor had already secured.
"She did something so horrible, I was like, 'Oh, we're just straight-up enemies.' And it wasn't even about a guy! It had to do with business. She basically tried to sabotage an entire arena tour. She tried to hire a bunch of people out from under me. And I'm surprisingly non-confrontational - you would not believe how much I hate conflict.
"So now I have to avoid her. It's awkward, and I don't like it."
As you'd expect, Taylor didn't specify who exactly she was talking about but the rumours are flying... we wonder if any female artists will come out with a response?!
'Bad Blood' will be featured on Taylor's upcoming fifth studio album 1989, which is scheduled for release om 27 October.
Watch Taylor's 'Shake It Off' video:
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