Engineering Duty Officer (EDO) is a term used predominantly in the United States Navy. It refers to a qualified engineering officer who manages the technical aspects of a ship's operation. EDOs are specifically responsible for overseeing the maintenance, repair, and operation of the vessel's engineering systems. While the abbreviation EDO is commonly used, there are several synonyms that could be used to refer to this job title. These include Marine Engineering Officer (MEO), Naval Engineering Officer (NEO), Marine Technical Officer (MTO), and Naval Technical Officer (NTO). Regardless of the synonym used, these officers play a crucial role in ensuring the safe and efficient operation of Navy vessels.