(I) won't tell a soul

(I) won't tell a soul

I won't reveal some confidential information to a single other person. A: "I heard Greg is getting fired, but I don't think even he knows yet." B: "Don't worry, I won't tell a soul." I'm so sorry, I didn't mean to pry! I won't tell a soul!
See also: soul, tell
Farlex Dictionary of Idioms.
See also:
  • all in (one's) head
  • don't even think about it
  • cast (one's) lot in with (someone or something)
  • cast lot in
  • don't get me wrong
  • bank on
  • banking
  • don't beat a dead horse
  • come it (with one)