sharp as a razor

(as) sharp as a razor

1. Literally, having an extremely sharp point or edge. Be careful picking up those shards of broken glass! They're as sharp as razors. No one but Mommy or Daddy is allowed to use this carving knife, OK Tommy? It's sharp as a razor, and could take your whole finger off if you're not careful!2. Very intelligent, witty, and quick-thinking. My grandmother's became very physically incapacitated as she grew older, but her mind was as sharp as a razor until the day she died. Of course Ellen is our valedictorian—she's sharp as a razor!See also: razor, sharp

sharp as a razor

 1. very sharp. (*Also: as ~.) The penknife is sharp as a razor. The carving knife will have to be as sharp as a razor to cut through this gristle. 2. and sharp as a tack very sharp-witted or intelligent. (*Also: as ~.) The old man's senile, but his wife is as sharp as a razor. Sue configure things out from even the slightest hint. She's as sharp as a tack.See also: razor, sharp