A person who obtains something through extortion; someone who uses threats or force to get money or valuables from others.
From 'extort' plus '-er' (suffix meaning 'one who does' an action). Directly derived from the verb 'extort.'
The '-er' suffix is so productive in English that you can almost always add it to a verb to make 'a person who does that'—though 'extortionist' is the more common word for this criminal.
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