Soft neighing sounds made by horses; to make these gentle sounds.
From Middle English 'nicke,' possibly imitative of the horse sound itself. Originally British dialect, became standard English for the specific soft vocalizations of horses.
Horses have an entire vocabulary of sounds—nickers are one of the most affectionate, used between mother horses and foals or horses greeting their owners, so the word captures a moment of gentleness in animal communication.
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