A person who shows disrespect to others; someone who is disrespectful.
From disrespect (verb) + -er (agent suffix). Literally means 'one who disrespects,' following the standard pattern of creating agent nouns in English.
We don't use this word much in modern English—we'd say 'disrespectful person' instead. But it's a perfect example of how English creates job-title-like words for actions (baker, maker, disrespecter).
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