Scattered messily or left with trash and garbage spread around carelessly; or when an animal gives birth to multiple young at once.
From Old French 'litiere' (straw bedding), related to 'lit' (bed)—originally meant laying down straw, evolved to mean scattered items like straw, then any scattered mess.
Litter used to be a cozy word about straw bedding in medieval times, but when streets got busy and people started throwing stuff around, the word followed the garbage down!
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