There are many synonyms for the phrase "blow open," which means to reveal or uncover something that was previously hidden or secret. Some common synonyms include "expose," "unmask," "reveal," "uncover," and "disclose." Other synonyms for this phrase might include "bring to light," "lay open," "lay bare," "throw wide," and "crack open." Whatever the wording, the concept remains the same: blowing open something that was once hidden, and letting it see the light of day for all to see. In many cases, this phrase is used to describe the act of exposing a wrongdoing, or bringing a hidden or illegal activity to the surface.