She warned him not to talk out of school about their relationship.
talk out of school
Frequency:
60
%
It's not professional to talk out of school about your colleagues.
talk out of school
Frequency:
45
%
He accidentally talked out of school and revealed their secret project.
Idiomatic Expressions for talk out of school
Phrase: talk out of school
Meaning: to reveal secret or confidential information
Usage: I trusted him with my personal problems, but he talked out of school and now everyone knows.