As sharp as a razor, extremely or ultimately sharp.(adjective)
Very clever or quick-witted.(adjective)
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Use "razor-sharp" in a sentence
"Last week, as I was minding my own business, grazing and tending to my beloved little fawn, I was cut down in the prime of my life, pierced through my heart by a razor-sharp arrow delivered by a barbaric human."
"During the ensuing months, Chen and Elfiki had become friends, with Chen learning that in addition to possessing a razor-sharp wit and a penchant for practical jokes, Elfiki harbored a competitive edge almost as deep-seated as her own."
"The castle had loaned us what appeared to be Victorian-era forceps, which were no match for the razor-sharp teeth on our pike."