flotilla
A small group of boats or ships traveling together.
A flotilla is a small fleet of boats or ships traveling together. You might see a flotilla of sailboats racing across a harbor during a regatta, or a flotilla of fishing boats heading out to sea at dawn.
Flotillas appear in both peaceful and military contexts. During World War II, a flotilla of small civilian boats helped rescue Allied soldiers trapped on the beaches of Dunkirk, France. Navies organize destroyers or patrol boats into flotillas for coordinated operations. On a summer lake, you might spot a flotilla of kayaks paddling together on an adventure trip.
The key idea is traveling together. A single boat isn't a flotilla. Even several boats near each other aren't really a flotilla unless they're moving or operating as a group. When your family goes canoeing with several other families and everyone paddles in formation down the river, you've formed your own little flotilla.
The word also captures something about size and scale. You wouldn't call a hundred warships a flotilla; that would be a full fleet or an armada. A flotilla is smaller and more manageable, the naval equivalent of a team rather than an army.