All articles starting with O

Ocreatus

Ocreatus, Gould 1846, is a genus of Andean racket-tail hummingbirds (Trochilidae). Once one species with eight subspecies, a 2016 Zootaxa revision split it into four species; current checklists recognize three: White-booted, Peruvian, and Rufous-booted Racket-tail.

Ocrelizumab

Ocrelizumab (Ocrevus, Ocrevus Zunovo) is a CD20-directed monoclonal antibody depleting B cells, FDA-approved March 2017 for relapsing and primary progressive multiple sclerosis, dosed 600 mg IV every 24 weeks.

Ocriplasmin

Ocriplasmin (Jetrea, microplasmin), a recombinant truncated human plasmin serine protease, treats symptomatic vitreomacular adhesion by enzymatic vitreolysis via a single 125 µg intravitreal injection; FDA-approved 2012, EU authorization withdrawn 2023.

OCRL

OCRL (OCRL1, Xq26.1) encodes inositol polyphosphate 5-phosphatase OCRL-1, which dephosphorylates PtdIns(4,5)P2 in the trans-Golgi network and endosomes. Loss-of-function variants cause Lowe syndrome and the milder Dent disease 2, both X-linked.

Ocrolus

Ocrolus Inc. is a New York-based document-automation software company for lending decisions in mortgage, small-business, and consumer credit. Founded in 2014, it raised an $80 million Series C in 2021.

OCS Group

OCS Group is a British-headquartered international facilities management company founded in 1900, employing over 130,000 people and controlled since 2022 by the private equity firm Clayton, Dubilier & Rice.

OCT Adventure Bay

OCT Adventure Bay (华侨城奇梦海滩水世界, Xiangyang Qimeng Beach Water Park) is an OCT Group water park in Xiangyang, Hubei, China, opened June 24, 2020; 150,000 m², 800 million yuan, four ocean-exploration themed areas, world's first Orbiter slide.

OCT East Knight Valley

Knight Valley (大侠谷) is the amusement park of the OCT East resort in Dameisha, Shenzhen, China, combining mountain canyon scenery with thrill rides like the Wood Coaster.

OCT East Tea Stream Valley

Tea Stream Valley (茶溪谷), leisure and tea-culture district of OCT East resort in Dameisha, Yantian District, Shenzhen; opened 2007 with Interlaken Town, Sanzhou Tea Plantation, Wetland Garden; served by a 12 RMB weekend bus line.

OCT Fantasy Valley

OCT Fantasy Valley (襄阳华侨城奇幻谷) is a space-exploration-themed theme park in Xiangyang, Hubei, opened April 2022 by OCT Group; 4 billion yuan, 450,000 m², six themed zones, B&M wing coaster DaVinci Ride.

OCT-ORION trial

OCT-ORION (NCT01742507) was a 2018 randomized optical coherence tomography trial in 60 multivessel-disease patients comparing Resolute Integrity durable-polymer zotarolimus-eluting and BioMatrix biodegradable-polymer biolimus A9-eluting stents; the durable-polymer stent showed better strut coverage with similar clinical outcomes.

Sep 19, 2026

Octabia

Octabia, also spelled Octaba, is a suppressed episcopal see of the Roman province of Byzacena in modern Tunisia, revived by the Catholic Church as a titular see in 1933.

Octabromodiphenyl ether

Octabromodiphenyl ether, also known as octaBDE or octabromodiphenyl oxide, is a brominated flame retardant used in ABS plastic electronics housings and phased out of production in 2004.

Octadecane

Octadecane, also called n-octadecane, is a straight-chain alkane with formula C₁₈H₃₈ that melts near 28 °C and is widely used as a phase change material.

Octadecylamine

Octadecylamine, also called stearylamine or 1-octadecanamine, is a white, waxy 18-carbon primary aliphatic amine (C₁₈H₃₉N) used as a film-forming corrosion inhibitor for steam systems and as a building block for cationic surfactants.

Octadecyltrichlorosilane

Octadecyltrichlorosilane (OTS) is a long-chain organosilane, CH₃(CH₂)₁₇SiCl₃, best known for forming self-assembled monolayers on glass, silicon dioxide, and mica, and used for water-repellent coatings and surface patterning.

Oct 20, 2026

Octadien 1 yl acetate

(Z,Z)-Octadien-1-yl acetate, EU pesticide substance ID 378, is a straight-chain unsaturated acetate ester pheromone-type compound, not approved in the EU, with a default MRL of 0.01 mg/kg.

Octagon

An octagon is a polygon with eight sides and eight angles; a regular octagon has 135° interior angles and is the shape of the stop sign.

Octagon house

An octagon house is an eight-sided dwelling briefly popular in the United States and Canada in the 1850s, promoted by phrenologist Orson Squire Fowler's 1848 book.

Octahedral molecular geometry

Octahedral molecular geometry is the arrangement of six atoms or ligands around a central atom at the corners of an octahedron, with 90° bond angles, as in sulfur hexafluoride.

Oct 22, 2026

Octahedral Pt–Ni oxygen-reduction nanocatalysts

Octahedral Pt–Ni oxygen-reduction nanocatalysts are octahedral platinum–nickel alloy nanoparticles whose {111} facets give high oxygen reduction activity, developed to cut platinum use in fuel cells.

Octahedron

An octahedron, also called a square bipyramid, is a polyhedron with eight triangular faces, six vertices, and 12 edges; the regular form is one of the five Platonic solids.

Octal

Octal, also known as base 8, is the numeral system using the digits 0 through 7, where each digit corresponds to three binary bits, used in Unix file permissions.

Octamer-binding transcription factor

Octamer-binding transcription factors (Oct1–Oct11; POU2F1/POU2F2/POU5F1 etc.) are POU-domain transcription factors binding the ATGCAAAT octamer motif, regulating embryogenesis, immunity, neurogenesis, stress responses, and disease.

Octamethylcyclotetrasiloxane

Octamethylcyclotetrasiloxane (D4) is a cyclic volatile methylsiloxane, a colorless liquid produced from dimethyldichlorosilane and used chiefly as a monomer for silicone polymers; it is now restricted in the EU.

Octamethylenediamine

Octamethylenediamine, also called 1,8-diaminooctane or 1,8-octanediamine, is an eight-carbon aliphatic diamine, H2N(CH2)8NH2, used as a monomer in nylon synthesis and as the main polyamine in the fungicide guazatine.

Octanal

Octanal, also known as caprylic aldehyde, is a saturated straight-chain aliphatic aldehyde, C8H16O, that occurs naturally in citrus oils and is used widely as a flavoring and fragrance ingredient.

Octane

Octane is a colorless, flammable alkane hydrocarbon with the molecular formula C8H18, occurring in crude oil and natural gas; its 18 isomers include n-octane and isooctane, the anchor of the gasoline octane rating.

Octane (Don Toliver album)

OCTANE is Don Toliver's fifth studio album, released January 30, 2026 on Cactus Jack/Donnway & Co/Atlantic; 18 tracks featuring Yeat, Rema, Travis Scott, Teezo Touchdown, and SahBabii; his first Billboard 200 number one.