A military cap having a close-fitting band, a round flat top sloping toward the front, and a visor. As originally worn by the French in Algeria about 1830 it was tall and stiff with a straight visor. It is now lower, has a curved visor, and is frequently soft.

Peaked cap. A Low shako with a leather peak. (Cassin). Originally a soft cap with a peak in front; later stiffened and given rows of braid to indicate the rank of the wearer. (Carman)

A military cap with a visor and a round flat top sloping toward the front (French képi, from German dialect (Switzerland) käppi cap)

A hat worn by both armies, originally of French design. It had a circular flat top, sloping toward the front, and a horizontal peak.

Adaptations and variations of the 1858 U.S. Army forage cap were colloquially and generally referred to as kepis. A French word derived from the Swiss-German diminutive for "cap," kepi usually denoted the French-style military cap with a short, round, flat crown and leather visor. In American Civil War use, it most often implied the Zouave-, chasseur-, or McClellan-pattern cap. The original 1858 forage cap had a taller crown flopping forward, in some cases its top standing almost vertical to the visor, and was used through the war in both armies. The chasseur model, close to the French cavalry fatigue hat, was a nattier number, its shorter crown pinched forward at about a 35 degree angle and its officer models decorated with a crown and band of contrasting colors and perhaps some gold braid around the top of the crown. Kepis are the hats most closely associated with Civil War service.

The kepi is a cap with a flat circular top and a visor. The word came into the English language from French, in which it is written with an acute accent: képi. It can be translated as "small cap".