Someone who bosses others around; a person who acts in a bossy or domineering manner, or one who holds a position of authority.
From 'boss' plus the agent suffix '-er' (one who performs an action). Modern English formation from the word 'boss' as a verb.
The word 'bosser' is interesting because it's not really a formal job title—it's more of a colloquial insult suggesting someone is overly domineering, which makes it more about personality than actual organizational position.
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