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Did Lady Gaga trade in her bizarre outfits for something a little more conservative like, say, a wedding dress?

Speculation of a secret marriage began swirling Tuesday after her longtime boyfriend, Taylor Kinney, was spotted wearing what appeared to be a wedding band on Instagram. The photo, posted by his "Chicago Fire" co-star Sophia Bush on her Instagram account, was laced with hashtags that may suggest that the two are more than just paramours.

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Along with the photo of the co-stars hugging, Bush wrote, "I'm REALLY excited to be on @nbcchicagofire tonight! Just about as excited as I was to see my buddy #TaylorKinney at our press day yesterday. Bear hugs are the best hugs. #ChicagoFire #ChicagoPD #ThatsHisPersonalRing #NotForTheShow #EveryoneCalmDown #LindsayAndSeverideArentMarried."

His personal ring? Hmm.

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The thought isn't as crazy as one may think. The "Bad Romance" singer was also spotted in July looking at what appeared to be wedding dresses with her mother in Toronto. While it's unknown if she was looking at the dresses for herself or if they were in fact wedding dresses, she and Taylor have been together for more than three years -- so anything is possible. And it wasn't the first time the mystery band has been spotted on Taylor. Back in May, the "Other Woman" star posted a pic on Instagram with his longtime love where he is sporting a similar band.

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While the couple are rarely seen together and rarely acknowledge their longtime relationship, last year she did call him "best friend." And last week, Gaga even took to Twitter, professing her love for her man and his TV show.

"Im SO PROUD+happy for all my buddies on @ChicagoFireNBC 9.4 million viewers, breaking the serious record! Go get 'em Taylor I love you!" she tweeted on Sept. 25.