Very tired and exhausted; worn out.
Possibly from 'poop deck,' the high stern deck of a ship, but origins are unclear. The modern sense of extreme tiredness became widespread in 20th-century American slang.
The origins of 'pooped' are mysterious—it might come from ships, or be influenced by German and Dutch, but nobody is entirely sure, which is unusual for such a common word and shows that sometimes even etymologists have to admit defeat.
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