The specialized language of seafarers is a complex mixture of the strange and the familiar, incorporating words from a variety of English dialects and foreign languages, and peppered with coined phrases and slang words. With its many intricate nuances, "navalese" is vitally important to a profession in which technical concepts need to be communicated briefly and accurately.

This dictionary defines and discusses more than 9000 nautical terms, abbreviations, slang expressions, customs and events, including terms now grown obsolete. Tables add detail about wind and wave measurements, notations, signals, navigation rules, rank and ratings.