Middle English faunen, from Old English fagnian "rejoice, be glad, exult, applaud," from fægen "glad" (see fain); used in Middle English to refer to expressions of delight, especially a dog wagging its tail (early 14c.), hence "court favor, grovel, act slavishly" (early 15c.). Related: Fawned; fawning.
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Definitions of fawning
attempting to win favor from influential people by flattery;