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A person who is always negative and looks constipated in appearance. Nothing makes them happy. You will notice that people avoid them like their attitude is contagious.
Any person of any age who can not be happy, EVER, in any circumstance.

Today my (husband or wife) got a raise at work and still a sour puss, such a grumungeon...
While at the bar a couple is being served an awesome appetizer with an amazing presentation, they look like someon died....such a couple of grumungeons.....
After meeting someone for the first time and they practically vomit nothing but negative conversation, "that dude is such a grumungeon"
by Calibrisella June 18, 2017
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