Pyramid

Origin

Middle French, French pyramide, piramide (in architecture) Egyptian funerary monument, building of a similar shape (c1160 in Old French), (in geometry) specific kind of polyhedron (1370), object or arrangement of objects in the shape of pyramid (15th cent.) and its etymon classical Latin pȳramid-, pȳramis (in post-classical Latin also piramis (11th cent. or earlier)) monumental structure built in ancient Egypt and used as a royal tomb, (in geometry) solid figure having the form of such a monument, any structure of this shape, natural object of this form < ancient Greek πυραμίδ-, πυραμίς monumental structure built in ancient Egypt and used as a royal tomb, (in geometry) solid figure having the form of such a monument, of unknown origin. Compare Old French piramz pyramidal shape (1272 in an apparently isolated attestation describing a bird of prey), Catalan piràmide (1617 as piràmida, originally in geometry), Spanish pirámide (1439 cent., originally in geometry), Portuguese pirâmide (late 16th cent.), Italian piramide (1292 describing the shape of a shadow, a1375 in architecture, a1537 in geometry); also Dutch piramide (1566), German Pyramide (1494), both originally in sense ‘Egyptian funerary monument’.

Ancient Greek πυραμίς is explained by some ancient authors as a derivative of πῦρ fire (see pyro- comb. form), on account of its pointed shape, by others as < πυρός wheat, grain, as if a granary. Compare ancient Greek πυραμίς kind of cake, which does derive < πυρός wheat, grain; it has been suggested that the word was used to denote an Egyptian monument as having the same shape as the cake, but the shape of the cake is otherwise unknown so this theory remains speculative. The suggested derivation from Egyptian pr-m-us height (of a pyramid) is doubtful.

The evidence of verse shows that in the early modern period the word showed plurals of two types: firstly (closely following the morphology of the Latin word) plural forms with stress on the second syllable, which were either quadrisyllabic (as in Latin) or trisyllabic (with the English plural ending -s, -es) (see α. forms); secondly, plural forms with stress on the first syllable (and with the English plural ending -s, -es) (see β. forms). In some cases (e.g. the Middle English form piramudes, which is attested only in prose) the assignment to α. or β. forms cannot be taken as definite.

• 1549

Definitions

• 1a : an ancient massive structure found especially in Egypt having typically a square ground plan, outside walls in the form of four triangles that meet in a point at the top, and inner sepulchral chambers

b : a structure or object of similar form

• 2: a polyhedron having for its base a polygon and for faces triangles with a common vertex
• 3: a crystalline form each face of which intersects the vertical axis and either two lateral axes or in the tetragonal system one lateral axis
• 4: an anatomical structure resembling a pyramid: as

a : any of the conical masses that project from the renal medulla into the kidney pelvis

b : either of two large bundles of motor fibers from the cerebral cortex that reach the medulla oblongata and are continuous with the pyramidal tracts of the spinal cord

• 5: an immaterial structure built on a broad supporting base and narrowing gradually to an apex <the socioeconomic pyramid>

Description

A pyramid (from Greek: "πυραμίς" – pyramis) is a structure whose outer surfaces (excluding the base) are triangular and converge at a single point. The base of a pyramid can be trilateral, quadrilateral, or any polygon shape, meaning that a pyramid has at least three triangular surfaces (at least four faces including the base). The square pyramid, with square base and four triangular outer surfaces, is a common version.

A pyramid's design, with the majority of the weight closer to the ground, and with the pyramidion on top means that less material higher up on the pyramid will be pushing down from above. This distribution of weight allowed early civilizations to create stable monumental structures.

For thousands of years, the largest structures on Earth were pyramids—first the Red Pyramid in the Dashur Necropolis and then the Great Pyramid of Khufu, both of Egypt, the latter the only one of the Seven Wonders of the Ancient World still remaining. Khufu's Pyramid is built entirely of limestone, and is considered an architectural masterpiece. It contains around 1,300,000 blocks ranging in weight from 2.5 tonnes (5,500 lb) to 15 tonnes (33,000 lb) and is built on a square base with sides measuring about 230 m (755 ft), covering 13 acres. Its four sides face the four cardinal points precisely and it has an angle of 52 degrees. The original height of the Pyramid was 146.5 m (488 ft), but today it is only 137 m (455 ft) high, the 9 m (33 ft) that is missing is due to the theft of the fine quality limestone covering, or casing stones to build houses and Mosques in Cairo. It is still the tallest pyramid. The largest pyramid by volume is the Great Pyramid of Cholula, in the Mexican state of Puebla.[1]