Engineman (abbreviated as EN) is a United States Navy occupational rating. Engineman was the former name for the current U.S. Coast Guard rating of Machinery Technician. ==History== Enginemen operate, service and repair internal combustion engines used to power some of the Navy`s ships and most of the Navy`s small craft. Most Enginemen work with.....
• (n.) A man who manages, or waits on, an engine.
En'gine·man noun ; plural Enginemen A man who manages, or waits on, an engine. 
a person who operates or helps to operate an engine or locomotive.