A creature or organism that defecates; technically any animal capable of eliminating waste, though rarely used outside scientific contexts.
From Latin 'defaecare' plus the agent suffix '-tor' (one who does). This forms a noun for anything performing the action, though the word is extremely rare in actual usage.
Defecator is technically correct for any living thing that poops—bacteria, flies, humans, whales—but you'll almost never see it used because it sounds absurdly formal for something so universal and everyday.
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