When you had a thing with a guy/girl and the two of you were very close and were almost practically dating but for some reasons you never ended up putting a label on it.
-You'll never guess who I just passed, my not-so-ex!

-Omg, that guy you had a thing with but never ended up dating?
-Yeah... Him... And just to be clear, the girl over there is the one who ruined our so-called relationship...
by ZophSoph July 4, 2020
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When you and a guy/girl had a thing and were almost dating, were very close, but for some reasons you did not end up together or putting a label on it
I saw my not-so-ex today...
Henry? The guy you had a thing with but you guys never ended dating...?
by ZophSoph June 30, 2020
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