In heraldry, an escutcheon is a shield that forms the main or focal element in an achievement of arms. The word can be used in two related senses. In the first sense, an escutcheon is the shield upon
Effigy of William Longespée the Younger (d.1250) in Salisbury Cathedral, showing an early triangular heater shield, the shape used as the "canvas" for the display of arms during the classical age of heraldry
Male (shield-shaped) and female (lozenge-shaped) coats of arms in relief in Southwark, London.
Console from Chichester tomb, Pilton, Devon, 1569
The heater shield or heater-shaped shield is a form of European medieval shield, developing from the early medieval kite shield in the late 12th century in response to the declining importance of the
Escutcheon (heraldry)
…shield used throughout the 11th and 12th centuries. By about the 1230s, shields used by heavy cavalry had become shorter and more triangular, now called heater shields. Transitional forms intermediate between kite and heater are seen in the late 12th to early 13th centuries. Transition to the heater was essentially…
Heraldic roll of arms displaying heater-shaped heraldic shields or escutcheons. Hyghalmen Roll, Germany, late 15th century