at (some time) sharp

at (some time) sharp

At an exact time, with the emphasis that one must not be late. We need to leave for the airport at 8 AM sharp tomorrow morning. Please be here at 6:30 sharp.
See also: sharp
Farlex Dictionary of Idioms.

at some time sharp

exactly at the time named. You must be here at noon sharp. The plane is expected to arrive at seven forty-five sharp.
See also: sharp, time
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • at some time sharp
  • in unison
  • chapter and verse
  • chapter and verse, cite/give
  • give chapter and verse
  • verse
  • emphasis
  • lay emphasis on
  • lay emphasis on (something)
  • then and there