de·ci·pher [ di sfər ](past and past participlede·ci·phered, present participlede·ci·pher·ing, 3rd person present singularde·ci·phers)
transitive verb
Definition:
1. make out what something says: to succeed in establishing what a word or piece of writing says when it is difficult or almost impossible to read
2. work out meaning of something: to study something that is written in code or in an unknown form of writing until it can be understood and read normally