To decipher means to figure out the meaning of something that's hard to read, understand, or interpret. When you decipher your friend's messy handwriting, you're working out what the scribbled letters actually say. When archaeologists decipher ancient symbols carved into stone tablets, they're unlocking messages written thousands of years ago.

The word often suggests that something is deliberately coded, encrypted, or just naturally difficult to understand. You might need to decipher a complex math problem by breaking it down step by step, or decipher the rules of a new board game by carefully reading the confusing instructions. Teachers sometimes struggle to decipher students' rushed test answers, and doctors are famously hard to understand when they write prescriptions that others then have to decipher.

While you can use decipher for anything confusing (like deciphering what your cat wants when it meows in the middle of the night), it works especially well for describing the process of cracking codes, translating unknown languages, or making sense of mysterious symbols. The word captures that satisfying moment when something confusing suddenly clicks and makes sense.