If you do not ~ that something is true, you do not tell anyone that it is true, and you keep it a secret. (INFORMAL)
She never ~ that anything was wrong...
I didn’t ~ to the staff what my conversation was...
He knows the culprit but is not letting on.
PHRASAL VERB: usu with brd-neg, V P that/wh, V P to n that/wh, V P