Mortarboard cap

The square academic cap, graduate cap, cap, mortarboard (because of its similarity in appearance to the mortarboard used by brickmasons to hold mortar) or Oxford cap, is an item of academic dress consisting of a horizontal square board fixed upon a skull-cap, with a tassel attached to the centre. In the UK and the US, it is commonly referred to informally in conjunction with an academic gown, as a "cap and gown". It is also sometimes termed a square,trencher, or corner-cap. The adjective academical is also used.

The cap, together with the gown and sometimes a hood, now form the customary uniform of a university graduate in many parts of the world, following a British model.

The mortarboard is generally believed by scholars to have developed from the biretta, a similar-looking hat worn by Roman Catholic (and High Church Anglican) clergy. The biretta itself may have been a development of the Roman pileus quadratus, a type of skullcap with superposed square and tump (meaning small mound). A reinvention of this type of cap is known as the Bishop Andrewes cap. The Italian biretta is a word derived from the Medieval Latin birretum from the Late Latin "large hooded cloak", which is perhaps of Gaulish origin, or from Ancient Greek πυρρός pyrrhos "flame-colored, yellow."

The cone-shaped red (seldom in black) biretta, related to the ancient Etruscan tutulus and the Roman pileus, was used in the fourteenth and fifteenth centuries to identify humanists, students, artists, and learned and blooming youth in general. The shape and the colour conveyed meaning: Red was considered for a long time the royal power, whether because it was difficult to afford vestments of such solid and brilliant dye or because the high symbolic meaning of blood and life, thus the power over life and death.

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