"'Swish Swish'—is that about anybody we know?" he asked, referring to her new song with Nicki Minaj.
Many people have speculated the track about Taylor Swift, with whom the pop star is reportedly feuding. Swift has not commented about the song, although Orange Is the New Black star Ruby Rose, a member of her "squad" of pals, dragged Perry over it.
"I think it's a great anthem for people to use whenever somebody's trying to hold you down or bully you," the singer told Fallon, raising her eyebrows.