The noun cappuccino denotes a type of coffee made with espresso and milk that has been frothed up with pressurised steam.

It was borrowed from Italian cappuccino, literally Capuchin, because the colour of this type of coffee resembles that of a Capuchin’s habit (similarly, the French noun capucin, literally Capuchin, is a name for the hare, from the colour of the animal’s fur); the Italian dictionary Treccani  defines colore cappucino as meaning:

marrone scuro, come la tonaca dei cappuccini
dark brown, like the Capuchins’ habit.

This advertisement for a hat called the Times Square, published in The Detroit Free Press (Detroit, Michigan) on 29^th September 1928, specifies that it is available in either

English Grey or Cappuccino Brown.

This use of cappuccino as a colour adjective has not been recorded in the Oxford English Dictionary (2^nd edition – 1989); in this dictionary, English cappuccino only appears in the sense of espresso coffee mixed with steamed milk, and the earliest instance is from This is San Francisco: A Classic Portrait of the City (Whittlesey House, New York, 1948), by the American journalist Robert O’Brien (1911-2004), who misidentified the colour referred to:

A step from the corner of Grant Avenue and Broadway is a café called “La Tosca.” Scenes from the opera are painted on the walls; Caruso sings from the juke box, and you drink a cappuccino, gray, like the robe of a capuchin monk, and made of chocolate that is laced with brandy or rum, and heated by steam forced through coffee.

The earliest instance of English cappuccino in this sense that I have personally found also dates from 1948 and is also from California; on 29^th April, The Press Democrat (Santa Rosa) published this advertisement:

MARICO’S
Newest Night Club
Opening Soon
4618 Redwood Highway North
4 Miles North of Santa Rosa
Featuring ITALIAN DINNERS
BY CHEF MARTINEZ
Formerly with Villa Chantecler
The Only Famous CAPPUCCINO North of San Francisco
WILL BE FEATURED AT THE BAR
See the Only Cappuccino Machine, Directly from Italy

ETYMOLOGIES

The English noun Capuchin, first recorded in the late 16^th century, denotes a friar belonging to a strict and autonomous branch of the Franciscan order founded in 1525.

This word is from the obsolete French form capuchin (now capucin), from Italian cappuccino, derived from capuccio, meaning capuche, hood, the friars being so named because of their sharp-pointed capuches.

The Italian noun cappuccio is in turn an augmentative of cappa in the sense of cloak with a hood; likewise, English cape originally denoted a Spanish cloak with a hood.