1. A term applied to a number of anatomic structures having a more or less pyramidal shape. SYN: pyramis [TA]. 2. A term denoting the petrous portion of the temporal bone. [G. pyramis (p.-), a p.]
- anterior p. SYN: p. of medulla oblongata.
- cerebellar p. SYN: p. of vermis.
- Ferrein p. SYN: medullary ray.
- Lallouette p. SYN: pyramidal lobe of thyroid gland.
- p. of light SYN: light reflex (3).
- Malacarne p. a lobule on the undersurface of the cerebellum, the posterior portion of the vermis.
- malpighian p. SYN: renal pyramids.
- p. of medulla oblongata an elongated, white prominence on the ventral surface of the medulla oblongata on either side along the anterior median fissure, corresponding to the position of fibers forming the corticospinal tracts. SYN: pyramis medullae oblongatae [TA], anterior column of medulla oblongata, anterior p..
- medullary p. SYN: renal pyramids.
- olfactory p. a small area of gray matter situated between the roots of the olfactory tracts; it is continuous caudally with the anterior perforated substance.
- petrous p. SYN: petrous part of temporal bone.
- population p. graphic representation of the age and sex composition of a population, constructed by computing the percentage distribution of the population in each age and sex class.
- posterior p. of the medulla SYN: gracile fasciculus.
- renal pyramids [TA] pyramidal masses seen on longitudinal section of the kidney; collectively, they constitute the renal medullae and contain part of the secreting tubules and the collecting tubules. SYN: malpighian p., medullary p., pyramides renales, pyramis renalis.
- p. of thyroid SYN: pyramidal lobe of thyroid gland.
- p. of vermis [TA] a subdivision of the inferior vermis of the cerebellum between the tuber and the uvula; vermis lobule VIII. SYN: cerebellar p., pyramis [TA] of cerebellum.
- p. of vestibule [TA] the upper triangular extremity of the crista vestibuli. SYN: pyramis vestibuli [TA].

* * *

pyr·a·mid 'pir-ə-.mid n
1) a polyhedron having for its base a polygon and for faces triangles with a common vertex
2) an anatomical structure resembling a pyramid: as
b) either of two large bundles of motor fibers from the cerebral cortex that reach the medulla oblongata and are continuous with the corticospinal tracts of the spinal cord
c) a conical projection making up the central part of the inferior vermis of the cerebellum

* * *

1. one of the conical masses that make up the medulla of the kidney, extending inwards from a base inside the cortex towards the pelvis of the kidney.
2. one of the elongated bulging areas on the anterior surface of the medulla oblongata in the brain, extending downwards to the spinal cord.
3. one of the divisions of the vermis of the cerebellum in the middle lobe.
4. a protrusion of the medial wall of the vestibule of the middle ear.

* * *

pyr·a·mid (pirґə-mid) [Gr. pyramis] a pointed or cone-shaped structure or part; called also pyramis [TA]. The term is often used alone to indicate the pyramid of the medulla oblongata.

Medical dictionary. 2011.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • Pyramid — Pyr a*mid, n. [L. pyramis, idis, fr. Gr. ?, ?, of Egyptian origin: cf. F. pyramide.] [1913 Webster] 1. A solid body standing on a triangular, square, or polygonal base, and terminating in a point at the top; especially, a structure or edifice of… …   The Collaborative International Dictionary of English

  • Pyramid — (обычно от англ. pyramid, заимствованное от греч. πυραμίς). Pyramid  музыкальный альбом филиппинской певицы Charice. Pyramid  видеоигра начала 1990 х годов, сходная с тетрисом. Pyramid  программный каркас для разработки веб… …   Википедия

  • Pyramid — Saltar a navegación, búsqueda Pyramid Álbum de The Alan Parsons Project Publicación Junio 1978 Grabación Septiembre 1977 Febrero 1978 Ab …   Wikipedia Español

  • pyramid — pyr·a·mid 1 / pir ə ˌmid/ n 1: a group of holding companies superimposed on one another to give those in control of the top holding company control over all of the companies with a small investment 2: the series of operations involved in… …   Law dictionary

  • pyramid — [pir′ə mid] n. [L pyramis (gen. pyramidis) < Gr, pyramid: replaced ME piramis, also < L] 1. any huge structure with a square base and four sloping, triangular sides meeting at the top, as those built by the ancient Egyptians for royal tombs …   English World dictionary

  • Pyramid — Studioalbum von The Alan Parsons Project Veröffentlichung 1978 Label Arista Records Format …   Deutsch Wikipedia

  • Pyramid — Pyr a*mid, v. i. (Speculation) To enlarge one s holding or interest in a series of operations on a continued rise or decline by using the profits to buy or sell additional amounts on a margin, as where one buys on a 10% margin 100 shares of stock …   The Collaborative International Dictionary of English

  • Pyramid — Pyr a*mid, v. t. (Speculation) To use, or to deal in, in a pyramiding transaction. See {Pyramid}, v. i. [Webster 1913 Suppl.] …   The Collaborative International Dictionary of English

  • pyramid — pyr‧a‧mid [ˈpɪrəmɪd] noun [countable] ORGANIZATIONS an organization with only a few people at the top, who have a lot of power and influence over those below them * * * pyramid UK US /ˈpɪrəmɪd/ noun [C] ► an organization or system that has few… …   Financial and business terms

  • pyramid — 1550s (earlier in L. form piramis, late 14c.), from Fr. pyramide (O.Fr. piramide, 12c.), from L. pyramides, pl. of pyramis one of the pyramids of Egypt, from Gk. pyramis (pl. pyramides), apparently an alteration of Egyptian pimar pyramid. Related …   Etymology dictionary

  • pyramid — ► NOUN 1) a monumental stone structure with a square or triangular base and sloping sides that meet in a point at the top, especially one built as a royal tomb in ancient Egypt. 2) Geometry a polyhedron of which one face is a polygon and the… …   English terms dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”