A nationally ranked college fencer is rattling his saber at Columbia University, suing the school for suspending him for fighting back against a female student who called him a “f-g,” court papers say.

The plaintiff — who identifies himself in Manhattan court papers only as “the #1 ranked Junior saber fencer in the U.S.’’ — says he was blocked from attending Columbia this spring because of his dispute with the 21-year-old woman in a residence-hall elevator.

The fencer says he was with some pals in the elevator when the woman complained that they were holding open the doors too long, yelling, “Get the f–k off the elevator, f–king drunken idiots, bunch of f-gs!’’

He said they later argued outside her room, and he blocked her arm as she went to hit him. She says he grabbed her neck and pushed her to the ground.