OMG!!! Taylor Swift and Calvin Harris ... TOGETHER!!???!

Taylor Swift and Calvin Harris surfaced in Nashville ... could it be?

Taylor and the famous DJ were coming out of Whole Foods Wednesday night -- wearing matching shirts no less -- when 2 people snapped the pics.

This isn't the first time they've been together recently. Taylor went to Calvin's concert in Vegas earlier this month. There were reports he chartered a jet to fly her to the gig.

They got all flirty at the Brit Awards after-party in London back in February.

Shopping for food together ... hmmm.