1. adjective Exposing, sharing, or revealing all the intimate, scandalous, or salacious details (of something). The aide agreed to give a tell-all interview about her affair with the senator.

2. noun Some piece of writing that exposes or reveals the intimate, scandalous, or salacious details (of something). The actor's tell-all about his experiences in the film industry has shot up to the top of the national bestseller list.