Navajo Code Talker Dictionary (navy.mil)
The Navajo Code was an encryption method used during the U.S. Pacific War against Japan beginning in 1942, based on using members of the North American Indian Navajo (also Diné) tribe as code talkers.
English terms not found in the Navajo language were compiled into a 274-word lexicon and replaced with words from the natural world.
In addition, a coded phonetic alphabet was created for the translation of less frequently used words and names.