When a guy...

A) Forgets girls he has hooked up with very easily.

B) Can delete a girl he has hooked up with or dated from his memory with great ease and efficiency and move on quickly.
"Man, John just totally dropped that cute Japanese girl yesterday and now he's got a new one. He has a serious case of girlnesia!"

"Did you hear that John tried to pick up this girl at a bar and it turns out he hooked up with her in the past - and he didn't remember! I'm afraid he has a bad case of girlnesia."
by james-sensei December 8, 2008
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