All articles starting with F
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Fourth Industrial Revolution
Fourth Industrial Revolution (4IR), also called Industry 4.0 or Industrie 4.0, is the proposed fusion of AI, robotics, IoT, and biotechnology across physical, digital, and biological domains, named by Klaus Schwab (2016) and rooted in Germany's 2011 initiative.
Fourth International
Fourth International: Trotskyist international founded by Leon Trotsky in 1938 with the Transitional Program; split in 1953, partially reunified in 1963 as the United Secretariat; today several rival organizations claim its legacy.
Fourth Mayawati ministry
Fourth Mayawati ministry: BSP government of Uttar Pradesh, India, 13 May 2007 to 15 March 2012, Mayawati's fourth term as chief minister, formed after BSP won 206 of 403 seats with 19 cabinet ministers, 20 ministers of state (independent charge), and 9 ministers of state.
Fourth Mongol invasion of Korea
The fourth Mongol invasion of Korea was a 1247 campaign by the Mongol Empire under Guyuk Khan against Goryeo, commanded by Amugan and ending with Guyuk's death in 1248.
Fourth N. Chandrababu Naidu ministry
Fourth N. Chandrababu Naidu ministry: Andhra Pradesh council of ministers formed 12 June 2024 under TDP chief N. Chandrababu Naidu after the 2024 election; 25 ministers from TDP, Janasena, and BJP, portfolios announced 14 June 2024.
Fourth Nattawat
Fourth Nattawat (Nattawat Jirochtikul, born 2004) is a Thai actor and singer under GMMTV and Riser Music, best known as the lead of the 2022 series My School President.
Fourth nerve palsy
Fourth nerve palsy, also called trochlear nerve palsy, is weakness of the cranial nerve supplying the superior oblique muscle, causing vertical double vision worse when looking down.
Fourth Partner Energy
Fourth Partner Energy is a Hyderabad-based Indian renewable energy company founded in 2010, developing distributed, open-access, and utility-scale solar and wind-solar hybrid projects for commercial and industrial customers.
Fourth Party System
Fourth Party System: period of US politics from the mid-1890s realignment (System of 1896) to 1932, marked by Republican dominance of the White House and Congress, the Bryan free-silver defeat, the 1912 Roosevelt split, and the Solid South.
Fourth Prose
Fourth Prose (Четвёртая проза) is a short confessional, denunciatory autobiographical essay by Osip Mandelstam, dictated to his wife in winter 1929/30 and left unpublished in his lifetime.
Fourth Reich
The Fourth Reich is a hypothetical successor to Nazi Germany's Third Reich and a political slogan. Used since 1944 in dystopian fiction, tabloid scares, post-1990 reunification fears, and populist claims that the EU is a German-dominated empire.
Fourth Republic of Ghana
The Fourth Republic of Ghana is the country's current political order, established on 7 January 1993 under the 1992 Constitution, with Jerry Rawlings as its first president.
Fourth Spanish Armada
Fourth Spanish Armada: Spain's 1597 invasion expedition under Martín de Padilla, Adelantado de Castilla, third armada of the Anglo-Spanish War after 1588 and 1596; it nearly reached Falmouth, England being undefended, but a gale scattered it and 108 of 136 ships returned.
Fourth television network
Fourth television network: any American broadcast network meant to join ABC, CBS, and NBC (the Big Three). Includes DuMont (1946-1955), Weaver's PSN, the 1967 United Network, and Fox, launched October 9, 1986, the first successful one.
Fourth voyage of Christopher Columbus
The fourth voyage of Christopher Columbus (1502 to 1504) was his last transatlantic expedition, seeking a westward passage to Asia along Central America and ending wrecked on Jamaica.
Fourth wall
The fourth wall is the imaginary boundary between performers and audience in a proscenium theatre; breaking it means actors or characters acknowledging the audience. Attributed to Diderot (1758), named by Jean Jullien; extends to film, TV, games, and books.
Fourth Way
Fourth Way, also called the Work, is G. I. Gurdjieff's spiritual teaching, systematized by P. D. Ouspensky, contrasting with the fakir, monk, and yogi paths and practiced within ordinary life.
Fourth Wing
Fourth Wing (2023) by Rebecca Yarros is the first book of the Empyrean romantasy series, following Violet Sorrengail at Basgiath War College's dragon-rider quadrant; a BookTok bestseller with a Prime Video adaptation ordered in 2026.
Fourth-generation fighter
A fourth-generation fighter is a jet combat aircraft designed in the 1970s and 1980s around pulse-Doppler radar and high maneuverability, including the F-15, F-16, MiG-29, and Su-27.
Fourth-generation warfare
Fourth-generation warfare (4GW): theory from Lind's 1989 Marine Corps Gazette article holding that war evolved through massed manpower, firepower, and maneuver into an evolved insurgency using all networks, and its critics.
Fourth-order gravity
Fourth-order gravity, also known as quadratic or higher-derivative gravity, is a class of modified gravity theories whose field equations contain derivatives of the metric up to fourth order.
Fourth-wave feminism
Fourth-wave feminism: proposed current feminist phase from the early 2010s, defined by digital and hashtag activism (#MeToo, #EverydaySexism), intersectionality, and backlash from the online manosphere; distinct from third-wave feminism by its online character.
Fourth, fifth, and sixth derivatives of position
The fourth, fifth, and sixth derivatives of position, called snap (jounce), crackle, and pop, extend the sequence of velocity, acceleration, and jerk; they appear in ride comfort studies and quadrotor trajectory planning.
Fourthline
Fourthline is an Amsterdam-based regtech company providing AI-driven identity verification, KYC, and AML compliance to banks and fintechs, co-founded by Krik Gunning and Chris van Straeten.
FouseyTube
FouseyTube (Yousef Saleh Erakat, يوسف صالح عريقات), American YouTube prankster born 1990 in Fremont, California; created fouseyTUBE in 2011, won a 2015 Streamy, later boxed, wrote a 2021 memoir, and streams on Kick since 2023.
Fouta Djallon (region)
Fouta Djallon (Fouta-Djalon, Futa Jallon) is an 81,952 km² sandstone highland region in central Guinea, 1,000–1,500 m high, source of the Niger, Senegal, and Gambia rivers, called West Africa's water tower, and historic seat of a Fulani imamate (1725–1896).
Fovea centralis
Fovea centralis: the tiny pit at the center of the macula of the retina, also called the fovea, where cones reach peak density with one-to-one wiring and no blood vessels, giving highest visual acuity; in mammals found only in haplorhine primates.
Fovea Investment Holdings, LLC
Fovea Investment Holdings, LLC is a Delaware investment holding company formed in 2024, tied to Cencora, which reported selling $800 million of a $1.24 billion equity offering in 2025.
Foveal hypoplasia-optic nerve decussation defect-anterior segment dysgenesis syndrome
FHONDA syndrome (foveal hypoplasia-optic nerve decussation defect-anterior segment dysgenesis) is a rare autosomal recessive eye disease caused by SLC38A8 mutations, with nystagmus, chiasmal misrouting, and severe foveal hypoplasia but no albinism-related hypopigmentation.
Fovinaciclib citrate capsules
Fovinaciclib citrate capsules (枸橼酸伏维西利胶囊, Futuoning) are a Chinese class 1 oral CDK4/6 inhibitor by Jinzhou Ahon/Fosun, NMPA-approved May 2025 with fulvestrant or aromatase inhibitors for HR+/HER2- advanced breast cancer.