All articles starting with P

Pyramidal peak

A pyramidal peak, also called a glacial horn, is a sharp pyramid-shaped summit formed when cirque glaciers erode a mountain from three or more sides; the Matterhorn is the type example.

Pyramidal tracts: cortical motor fiber systems (corticospinal and corticobulbar tracts) passing through the medullary pyramids; about 75-90% decussate, controlling voluntary movement, with lesions causing contralateral weakness.

Pyramiden (Пирамида)

Pyramiden (Пирамида, "the Pyramid") is a former Soviet coal-mining settlement on the Billefjorden in central Svalbard, Norway, abandoned as a mining community in 1998 and now visited by tourists as a preserved ghost town.

Pyramiden/Hoeyriggen (HP Disko Island)

Pyramiden (Hoeyriggen), highest point of Disko Island, Greenland: a 1,904 m basalt peak of the Maligât Formation in northeastern Disko, first climbed 22 July by an Italian party; distinct from East Greenland and Svalbard namesakes.

Pyramidion

Pyramidion (benbenet): the capstone of an Egyptian pyramid or the pyramid-shaped tip of an obelisk, a miniature of the benben stone of Heliopolis. Surviving examples include the basalt pyramidion of Amenemhat III and Hatshepsut's red granite obelisk tip.

Sep 19, 2026

Pyramidion of Amenemhat III

The Pyramidion of Amenemhat III is a dark stone capstone from the king's mudbrick pyramid at Dahshur, Egypt, now displayed in the Egyptian Museum in Cairo.

Pyramids FC

Pyramids FC (بيراميدز), Cairo club founded 2008 as Al Assiouty Sport, rebranded 2018; won 2025 CAF Champions League, 2025 CAF Super Cup, and FIFA African-Asian-Pacific Cup under Krunoslav Jurčić.

Sep 19, 2026

Pyramids of Meroe

The Pyramids of Meroe, or Begrawiya pyramids, are a royal cemetery in Sudan where Meroitic kings and queens were buried from the 3rd century BC.

Pyramids of Queens

Pyramids of Queens: the small queens' pyramids of Egypt's Fourth Dynasty at Giza, chiefly GI-a, GI-b, and GI-c east of Khufu's Great Pyramid, and the three beside Menkaure's pyramid.

Pyramus

Pyramus, extinct bivalve mollusk genus (Megadesmidae, Pholadomyida) named by Dana in 1847 from Wilkes expedition shells in Australia; Carboniferous to Permian, cold Gondwanan seas, type species P. myiformis.

Pyramus and Thisbe

Pyramus and Thisbe are forbidden Babylonian lovers in Ovid's Metamorphoses who die by suicide through a fatal misunderstanding, turning the mulberry's white berries red, and later inspire Shakespeare.

Pyramus Fossae

Pyramus Fossae: IAU-named system of narrow sinuous troughs in northwestern Utopia Planitia, Mars; 298 km across, centered 50.39N 66.31E, approved 1985 from an Antoniadi albedo feature, of debated glacial or soft-sediment origin.

Pyran

Pyran is a six-membered non-aromatic heterocycle, formula C₅H₆O, with two double bonds and two isomers, 2H-pyran and 4H-pyran, that appears in natural products like sugars and flavonoids.

Oct 20, 2026

Pyranocoumarin

Pyranocoumarin: a coumarin with a fused pyran ring; natural linear, angular, and condensed forms from Apiaceae and Rutaceae; also CAS 518-20-7, an unapproved EU rodenticide substance.

Pyranometer

A pyranometer is a radiometer that measures solar irradiance on a plane surface from the hemisphere above, the standard instrument for global horizontal irradiance in meteorology and solar energy.

Pyranose

A pyranose is the six-membered cyclic ring form of a monosaccharide, a hemiacetal or hemiketal based on the heterocycle pyran, with terms introduced by Norman Haworth in the 1920s.

Pyrantel

Pyrantel (pyrantel pamoate) is a tetrahydropyrimidine anthelmintic, a nicotinic acetylcholine agonist, used OTC for pinworm at 11 mg/kg and against soil-transmitted helminths; resistance reported in Ancylostoma caninum.

Oct 20, 2026

Pyrasulfotole

Pyrasulfotole (CAS 365400-11-9, AE 0317309) is a pyrazolone HPPD-inhibitor herbicide for broadleaf weed control in cereals, used at 25–50 g ai/ha with bromoxynil or MCPA and the safener mefenpyr-diethyl.

Pyrazinamide

Pyrazinamide is a first-line oral antibiotic used to treat tuberculosis, valued for killing slow-growing bacilli; its addition in the 1970s shortened treatment from 12 to 6 months.

Pyrazine

Pyrazine, also known as 1,4-diazine, is an aromatic heterocyclic organic compound with formula C4H4N2, occurring naturally in roasted foods and used as a flavoring agent.

Pyrazole

Pyrazole, also known as 1,2-diazole, is an aromatic heterocyclic compound with a five-membered ring of three carbons and two adjacent nitrogens, found in over 50 marketed drugs and many pesticides.

Pyrazophos

Pyrazophos (CAS 13457-18-6), an organophosphorus systemic fungicide of the pyrazolopyrimidine class, controls powdery mildews on cereals, cucurbits and fruits; not EU-approved, ADI 0.004 mg/kg bw, pro-fungicide converted to PP.

Pyrazoxyfen

Pyrazoxyfen (SL-49, Paicer) is a pyrazole proherbicide herbicide from Ishihara Sangyo Kaisha, commercialized 1985 for rice weeds; it inhibits HPPD via its hydroxypyrazole metabolite and is no longer EU-approved.

Pyre

Pyre: a heap of wood or other combustibles on which a dead body is burned as a funeral rite, from Greek pyr (fire). Covers etymology, ancient Greek, Roman, Iberian and Hindu pyre cremation, the 9,500-year-old Malawi pyre, and modern legality in Colorado, the UK Ghai ruling, Trinidad and Seychelles.

Pyre (video game)

Pyre is Supergiant Games' 2017 party-based RPG for PC and PS4, blending a branching visual-novel story with three-on-three Rites matches in the Downside; no game-over, Metacritic 82.

Pyrene

Pyrene is a polycyclic aromatic hydrocarbon, C₁₆H₁₀, made of four fused benzene rings, a colorless crystalline solid with blue fluorescence found in combustion products and used widely as a fluorescent probe.

Pyrenean brook salamander

Pyrenean brook salamander (Calotriton asper, formerly Euproctus asper), an aquatic salamandrid endemic to Pyrenees streams and lakes in France, Spain, and Andorra; Near Threatened, threatened by climate change, trout introduction, and damming.

Pyrenean ibex

Pyrenean ibex (bucardo, Capra pyrenaica pyrenaica), extinct Pyrenean subspecies of Iberian ibex; last female Celia died 2000; cloned briefly in 2003; related subspecies reintroduced in French Pyrenees.

Pyrenean Mastiff

Pyrenean Mastiff (Mastín del Pirineo, Mastín d'Aragon), a giant Spanish livestock guardian dog from the Aragonese Pyrenees; FCI-recognized 1954, white coat with mask and patches, minimum 77 cm at the shoulder, distinct from the Great Pyrenees and Spanish Mastiff.