From Longman Dictionary of Contemporary Englishkeep a secretkeep a secretTELL A SECRETto not tell anyone about a secret that you know Can I trust you to keep a secret? → keep
Examples from the Corpus
keep a secret• Can you keep a secret?• Most humans are not very good at keeping secrets.• The private key, used to encrypt transmitted information by the user, is kept secret.• The public key is used to decrypt information at the receiver and is not kept secret.• The state gave them to visiting businessmen whose names are being kept secret.• What happened a few miles away was kept secret.• Zhang was killed instantly, although his death was kept secret for a few days.• The relationship was not kept secret from her supervisors.• Richie was in the know but the plan was kept a secret from Midge and Stevie. 