The tricorne, or tricorn, is a style of hat that was popular during the 18th century, falling out of style shortly before the French Revolution. At the peak of its popularity, the tricorne was worn both by civilians and as part of military uniform.

The black-coloured tricorne has a rather broad brim, pinned up on either side of the head and at the back, producing a triangular shape. The hat was typically worn with the point facing forward on the head. The crown is low, unlike the steeple hats worn by the Puritans or the stovepipe hat of the nineteenth century.

Tricornes ranged from the very simple and cheap to the extravagant, occasionally incorporating gold or silver lace trimming and feathers. The tricorne later evolved into the bicorne and eventually the cocked hat.

Tricornes survive today as part of the traditional dress of the Chelsea Pensioners and the Guardia Civil of Spain.