don't let it out of this room

don't let it out of this room

Don't reveal this information to anyone else. Greg got the promotion, but don't let it out of this room—the boss will officially announce it later today.
See also: let, of, out, room, this
Farlex Dictionary of Idioms.
See also:
  • (I) won't tell a soul
  • don't get me wrong
  • don't beat a dead horse
  • all in (one's) head
  • (someone's) secret is safe with (one)
  • at the drop of a hat
  • come it
  • come it (with one)
  • don't go there