when a girl is aroused, it gives the effect of a phantom boner. It's like having a boner, only girls don't have penises, so they get phantom-boners.
Beth: "aaron and luke were so hot when they were making out!"
Becky: "I know! I got a phantom-boner!"
Becky: "I know! I got a phantom-boner!"
by Jake-Off September 04, 2007