English-speaking people have referred to groups of ships as fleets for centuries. The origin of the word traces back to the Old English "fleotan," which meant to float or to swim.
A fleet of ships is most often a group of vessels sailing together under one military commander or as part of the same privately owned company. In modern times, the term can refer to a group of motor vehicles and even aircraft. According to the Federation of American Scientists, the term "flotilla," which means "small fleet," is also used by mariners and the U.S. Navy, among other nautical organizations.