A person who shows excessive or insincere flattery and attention to gain favor; someone who behaves obsequiously.
Agent noun from 'fawn' plus '-er,' following English's standard pattern for creating 'one who does X.' The term became increasingly common during periods of court politics where flattery was survival strategy.
Shakespeare's characters frequently called flatterers 'fawners'—the Elizabethan court was filled with them, and the metaphor of a dog or young deer fawning (crouching submissively) perfectly captured the servile behavior Renaissance writers despised.
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