1 definition by Frodo_the_Wise
A girl that you care about very much and she cares about you too but for some reason, past experiences etc. She is too terrified to commit to being your "Girlfriend". You are exclusive, you do most of the things you would do with a "Girlfriend" just don't sport the title yet.
Who was that beautiful girl you were with at the movies last night? That was Nat, she's my "not-Girlfriend".
by Frodo_the_Wise February 23, 2016