The Scottish DJ sings on the track, and he discussed the meaning of the lyrics in an interview with iHeartRadio on Thursday.
"[The] song's kind of about breaking out of a situation that you thought was a good thing. Then you're way more comfortable out of it. And it could be anything. It could be a job or it could be a relationship," he said. "I kind of had the idea for the concept for a few years, but I didn't know how to work out how it sounded."
The lyrics for the song include lines such as, "Why wait to say, at least I did it my way? Lie awake two-faced, but in my heart I understand," and, "I made my move and it was all about you. I feel so far removed. You are the one thing in my way."
Harris, 32, and the "Bad Blood" singer, 26, split in June after dating for 15 months, and Swift quickly rebounded with Thor star Tom Hiddleston (as Us Weekly exclusively reported earlier this month, they have since gone their separate ways).
The split between the Grammy winner and Harris was not completely amicable — Harris went off on the pop star in July after it was revealed that she wrote the lyrics and melody for his hit "This Is What You Came For," which features Rihanna.
The music producer later said he regretted lashing out at his ex.
"It was completely the wrong instinct. I was protecting what I see as my one talent in the world being belittled," he told British GQ earlier this month. "It felt like things were piling on top of me, and that was when I snapped. I'm not good at being a celebrity, but when it ended, all hell broke loose. Now I see that Twitter thing as a result of me succumbing to pressure. It took me a minute to realize that none of that matters. I'm a positive guy."
Fans tweeted their theories about Harris' new song being a dig at Swift, who has famously dissed her exes in her songs.
"Calvin Harris playing Taylor Swift at her own game with his new tune," wrote one commenter.
"So Calvin Harris has just released a song about Taylor Swift #Karma #WhatGoesAroundComesAround," tweeted another.
"'You were the one thing in my way,' @CalvinHarris repeats over and over, oops!! Is he singing to @taylorswift13," another wrote, while a Swift fan warned, "@CalvinHarris If that's the case, wait 'til @TaylorSwift13 releases a complete album .. Just for you, oh oh .. #MyWay."
Other fans weren't convinced the song was about her at all. "Honestly I'm not even sure it's about her. I felt like it could have been about his career," one person wrote on Tumblr.
Listen to the track and check out the lyrics in the video above.
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