The term monumental sculpture is often used in art history and criticism, but not always consistently. It combines two concepts, one of function, and one of size, and may include an element of a third more subjective concept. It is often used for all sculptures that are large. Human figures that are perhaps half life-size or above would usually be considered monumental in this sense by art historians, although in contemporary art a rather larger overall scale is implied. Monumental sculpture is therefore distinguished from small portable figurines, small metal or ivory reliefs, diptychs and the like.