break a code

break (a/the) code

To determine or decipher a secret code. It is imperative that we break the enemy code and access their plans. She definitely broke the code on my phone—her picture is suddenly my new background!
See also: break, code

break a code

to figure out a code; to decipher a secret code. The intelligence agents finally broke the enemy's code. When they broke the code, they were able to decipher messages.
See also: break, code