There are many synonyms for the phrase "tell-all" which means revealing information that is usually considered private or secret. Some common synonyms include "confessional," "exposing," "disseminating," "disclosing," "unveiling," "uncovering," "revealing," "betraying," "divulging," "spilling the beans," "letting the cat out of the bag," "blabbing," and "outing." These phrases all imply that someone is sharing information that they should not be sharing, whether intentionally or not. The use of a synonym for "tell-all" depends on the specific context and tone of the situation, but each carries the same implication of revealing something that is not meant to be public knowledge.