pennant number, a number used to identify ships by the modern Royal Navy and other navies of Europe and the Commonwealth.

Jermaine Pennant, an English Football player, currently playing for Liverpool F.C.

Pennant (commissioning), the traditional sign of a warship, flown from its masthead while the ship is in commission.

pennant race, the last few weeks of the regular American professional baseball season

Thomas Pennant, a Welsh naturalist and antiquary

A reference to the pennant-shaped "No Passing Zone" prohibitory traffic sign found in the United States.

pennon, a narrow, tapering flag commonly flown by ships at sea:

The common name for the Genus of dragonfly known as Celithemis

pennant (sports), a commemorative flag displayed or flown by a league-winning team

Pennant (church), flown by navies during services on board ships.

Broad pennant, flown from the masthead of a Royal Navy ship to indicate the presence of a commodore on board.