The naval officer in command of a military ship WordNet 3.0 & Open English WordNet

Captain is the name most often given in English-speaking navies to the rank corresponding to command of the largest ships. Wikipedia

Rank corresponding to command of the largest ships in English-speaking navies Wikipedia Disambiguation

The name most often given in English-speaking navies to the rank corresponding to command of the largest ships Wikipedia Disambiguation

Naval military rank Wikidata

A commissioned officer in the United States Navy, Coast Guard, NOAA Corps, or PHS Corps of a grade superior to a commander and junior to a rear admiral (lower half). A captain is equal in grade or rank to an Army, Marine Corps, or Air Force colonel. Wiktionary