Decayed or decomposed, usually due to age or bacterial breakdown; or morally or politically corrupt.
From Old English 'rotian' (to rot), likely from Proto-Germanic roots meaning decay. Used both literally for decaying matter and metaphorically for corruption since medieval times.
One of English's most visceral words—'rotted' has a sound that matches its meaning, which linguists call 'onomatopoeia' or 'sound symbolism.' The hard 't' sounds make it feel uglier than the smoother 'decomposed,' which is why Shakespeare used 'rotted' to describe moral corruption.
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