One who dismembers; a person or thing that tears apart or separates something into pieces.
From dismembrate plus the -or suffix (variant of -er), forming an agent noun; the -or ending comes from Latin and typically indicates someone who performs an action.
While grammatically sound, 'dismembrator' almost never appears in real texts—it's one of those perfectly logical English words that nobody actually uses because 'dismemberer' sounds more natural, showing that not every possible word construction succeeds in a language.
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