This person usually will have an even story or event worse than the situation you are or have experienced. The opposite of a "one-upper"
I was telling Maria about how I wrecked my motorcyle last week and Crystal, the one-downer, proceded to explain how she was in an accident and lost her leg, punctured a lung and apparenly the hospital food was shiite and came back to life as hedgehog..
by thomas curtis June 17, 2008
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An annoying person who responds to hearing someone else’s experience or problem by immediately telling a similar story about themselves with a much less interesting or boring corresponding story. (Note: The story will be much longer than you could ever imagine or want)
Person: Last summer I went to Thailand and rode on an elephant.
One Downer: Last summer I rode my horse in my backyard while my brother watched. My brother also rode the horse. then we went inside my house and had a sandwich.
by Beatreese October 12, 2009
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(n.) Someone who tries constantly to out-do your bad personal experiences with their own bad stories, which in their eyes, is always worse.
Me: Oh man, I just had the worst day at work! I got fired...

Tim: Oh, sorry about that. Mine wasn't too much better. I forgot to save a really long document before shutting down my computer. Such a bad day!
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Tim's a clear one-upper downer
by The Communicator November 11, 2009
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