kiss and tell

kiss and tell (third-person singular simple present kisses and tells, present participle kissing and telling, simple past and past participle kissed and told)

1. To betray a confidence by disclosing private information, especially of a sexual nature.
   • 2007, Robert Ayres Carter, Nobody yet Knows Who I Am: A Personal History: 1943-1953, Xlibris Corporation (→ISBN), page 34:

     While I told Joe all about my Beth, and he told me about his Ellen, a student at Northwestern, I did not go into any details about my sex life; I have never liked to kiss and tell, even though I suppose that's what I'm doing in these pages.

• kiss-and-tell

• tell tales out of school

• “kiss_and_tell” (US) / “kiss_and_tell” (UK) in Oxford Dictionaries, Oxford University Press.
• “Kiss and tell” in Gary Martin, The Phrase Finder, 1997–.