Mock title used to refer to an authoritative, bossy or demanding person.(noun)
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Use "his nibs" in a sentence
""Yes, comes for all summer," replied "Banty" Clark, "and I've got to be polite and show him around, and, I suppose, stay in the ranch house all the hot weather while his nibs togs up in his London clothes, 'don't yer know,' and drinks five-o'clock tea, and does nothing but stare at the toes of his patent leather shoes."