Anything that harkens back to the past is fantasy. But these days that's not absolute. You're going to get blendings and mixings. People are mixing up the genres more and more, which I think is good. It's great stuff.
Fantasy is a much bigger world than it used to be.
It's a much bigger world than people realize. My books are mystery crossovers though they have elements of other genres as well - horror, some romance, but essentially mysteries. My character is essentially a detective in a medieval setting with magic available in limited quantities. They're not magical themselves. I sort of shy away from that because it makes things too easy.