All articles starting with F

Fidanacogene elaparvovec

Fidanacogene elaparvovec (Beqvez, fidanacogene elaparvovec-dzkt) is Pfizer's AAVRh74var gene therapy expressing FIX-Padua for moderate to severe hemophilia B; FDA-approved April 2024, EU authorization withdrawn May 2025.

Fidaxomicin

Fidaxomicin (Dificid, Dificlir), an 18-membered macrocyclic lactone antibiotic from Dactylosporangium aurantiacum, treats C. difficile infection by inhibiting RNA polymerase; FDA-approved 2011 (adults) and 2020 (children), preferred first-line over vancomycin since 2021 IDSA/SHEA guidelines.

Fidchell

Fidchell (fithcheall, fidhcheall; Welsh gwyddbwyll) was the principal board game of early medieval Ireland, a skill-only battle game with equal sides and custodial capture, likely derived from Roman ludus latrunculorum; its rules are lost and all modern versions are reconstructions.

Fiddle

A fiddle is a bowed string instrument identical to the violin; the name marks folk, dance, and traditional contexts (Irish, Scottish, bluegrass, Cajun) rather than construction, with Old English fiðele roots first recorded in 1205.

Fiddlehead

Fiddlehead, or crozier, the coiled young fern frond formed by circinate vernation; also the edible spring shoot of the ostrich fern (Matteuccia struthiopteris), which must be boiled 15 minutes or steamed 10-12 minutes before eating.

Fiddler crab

Fiddler crabs (Ocypodidae, formerly genus Uca) are small semi-terrestrial crabs of world mudflats and salt marshes; males wave one enlarged claw, up to half body weight, to court females and fight rivals, while all crabs dig burrows used for shelter, breeding, and hibernation.

Fiddler on the Roof

Fiddler on the Roof: 1964 Broadway musical by Bock, Harnick, and Stein, based on Sholem Aleichem's Tevye stories; 3,242 performances, nine Tonys, six Broadway productions, Yiddish and Regent's Park revivals.

Fiddler on the Roof (film)

Fiddler on the Roof (1971), Norman Jewison's film of the Bock-Harnick-Stein Broadway musical, stars Topol as Tevye the milkman in Tsarist Russia; it won three Oscars from eight nominations and grossed over $38 million.

Fiddler's Ferry power station

Fiddler's Ferry power station was a coal-fired power station on the River Mersey between Widnes and Warrington, Cheshire, generating electricity from 1971 until its closure on 31 March 2020.

Fiddler's Green

Fiddler's Green is a sailors' paradise in 19th-century English maritime folklore, recorded by 1825, where sailors who die ashore enjoy endless rum, tobacco, music, and company after death.

FIDE

FIDE (Fédération Internationale des Échecs), the International Chess Federation, founded 1924 in Paris, headquartered in Lausanne; world governing body of chess regulating competitions, ratings, and titles, with 204 member federations and IOC recognition since 1999.

FIDE Freestyle Chess World Championship 2026

The FIDE Freestyle Chess World Championship 2026 was the first official Freestyle Chess (Chess960) world championship, staged at Weissenhaus, Germany, and won by Magnus Carlsen, who defeated Fabiano Caruana 2.5–1.5 in the final.

FIDE Grand Prix 2022

FIDE Grand Prix 2022: three 16-player knockout-pool chess tournaments in Berlin and Belgrade, February-April 2022. Hikaru Nakamura won the series, Richard Rapport was runner-up; both qualified for the 2022 Candidates Tournament in Madrid.

FIDE titles

FIDE titles: permanent designations by the International Chess Federation, including GM, IM, FM, CM and women's WGM–WCM player titles earned via norms, ratings, or direct titles, plus FIDE Arbiter and International Arbiter titles.

Fidel Castaño

Fidel Castaño, or Fidel Antonio Castaño Gil, was a Colombian cattle rancher, drug trafficker, and paramilitary leader whose army grew into the ACCU and later the AUC.

Fidel Castro

Fidel Castro (Fidel Alejandro Castro Ruz, 1926-2016), Cuban revolutionary who overthrew Batista in 1959, ruled Cuba as prime minister then president for nearly five decades, built a socialist state aligned with the Soviet Union, and left a polarized legacy of social gains and repression.

Fidel Castro Díaz-Balart

Fidel Castro Díaz-Balart (1949–2018), called Fidelito, eldest son of Fidel Castro, was a Cuban nuclear physicist trained in the USSR who led Cuba's Juragua nuclear program and later served as Scientific Advisor to Cuba's Council of State.

Fidel Edwards

Fidel Henderson Edwards (born 1982, Barbados), nicknamed Castro, is a West Indian right-arm fast bowler with a slingy action; five-wicket Test debut 2003, career-best 7/87, 165 Test wickets, later Hampshire and T20 franchise career.

Fidel V. Ramos

Fidel V. Ramos (FVR, 1928–2022), 12th president of the Philippines 1992–1998, career general and 1986 EDSA defector; led Philippines 2000 reforms, ended the power crisis, and signed the 1996 MNLF peace agreement.

Fidelio

Fidelio (Leonore) is Ludwig van Beethoven's only opera, a German rescue opera in three versions (1805, 1806, 1814) with four overtures, in which Leonore disguised as Fidelio frees her husband Florestan from Pizarro's prison.

FIDELIO-DKD trial

FIDELIO-DKD was a phase III, placebo-controlled trial sponsored by Bayer that found finerenone lowered the risks of chronic kidney disease progression and cardiovascular events in type 2 diabetes.

Fidelipac

Fidelipac is an endless-loop magnetic tape cartridge, also called the NAB cartridge or "cart", used in radio broadcasting from 1959 into the late 1990s for commercials and jingles.

Fidelis Gadzama

Fidelis Gadzama, Nigerian 400m sprinter born 1979, won Olympic gold in the 4x400m relay at Sydney 2000 after the USA's disqualification; personal best 45.59.

Fidelites

Fidelites is an extinct genus of Devonian ammonoid cephalopods in the family Agoniatitidae, established in 1983 and known from the Eifelian of Bohemia, Morocco, and Algeria.

Fidelity (quantum mechanics)

Fidelity in quantum mechanics measures how similar two quantum states are, from 0 to 1, and is used to benchmark teleportation, quantum gates, and prepared states.

Fidelity Investments

Fidelity Investments, also known as FMR Corporation, is a privately held Boston financial services firm combining asset management, brokerage, and 401(k) recordkeeping, controlled by the Johnson family.

Oct 10, 2026

Fidelity National Financial

Fidelity National Financial, Inc. is a Jacksonville, Florida-based holding company and the largest US title insurance group, holding a 32% market share through five underwriters.

FidelityFX

FidelityFX is AMD's open-source suite of image-quality and rendering-effect technologies, distributed through GPUOpen; its Super Resolution (FSR) upscaler competes with Nvidia's DLSS and Intel's XeSS.