Decrypt

1. [A] generic term encompassing decode[?] and decipher.

2. To convert encrypted text into its equivalent plain text by means of a cryptosystem[?]. (This does not include solution by cryptanalysis.)

Note: The term "decrypt" covers the meanings of "decipher" and "decode."

Source: from Federal Standard 1037C and from the National Information Systems Security Glossary and from the Department of Defense Dictionary of Military and Associated Terms