Someone that ditches/leaves their friends.
Also, someone that backs out of plans that they arrange.
Chris: Let's go to Applebee's.
Matt: I can't. I have diarrhea.
Tanner: Okay. Sleepover at my house.
Matt: I can't. I have diarrhea.
Chris and Tanner (in unison): You're such a ditcher.
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