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Not using your primary girlfriend or boyfriend for having sex with. Using a ho or a pro when when you can't be with your main chick.
1: Looks like I have to rely on my backup sex this weekend.

2: Where is Rachel?

1: She's out of town all this week.
by AdmiralIII May 19, 2009
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Jul 2 Word of the Day
Someone people turn to when they're sad who makes them feel better.
Dude, I was so unhappy about my girl, until I spoke to my serotonin donor who really helped me feel better
by jonfurstn1 November 27, 2009
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