A person who negotiates or haggle over prices and terms in a deal.
From 'bargain' plus '-er' (from Old English), a productive suffix creating agent nouns (one who performs an action). The base 'bargain' comes from Old French via Germanic roots.
The '-er' suffix is perhaps English's most prolific word-creator—you can add it to almost any verb to name the person who does it, which is why we have 'teacher,' 'singer,' 'builder,' and yes, 'bargainer.'
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