Search by letter: A
Search by letter
Search by letter: A
- Archie Thompson
- Archignat — Commune in the Allier department of central France Archignat
- Archimedean solid
- Archimedes of Syracuse: Life, Work, and Legacy Archimedes
- Archimedes number
- Archimedes' principle: buoyancy, displaced fluid, and practical applications Archimedes' principle
- Archimedes' screw
- Archipelago: formation, types, ecology and human significance Archipelago
- Archipelago of San Andrés, Providencia and Santa Catalina
- Architect: role, skills, history, and significance Architect
- Architectural, Surveying, Planning and Landscape (Hong Kong functional constituency) Architectural, Surveying, Planning and Landscape (constituency)
- Architecture: Art, Science, and the Design of Built Environments Architecture
- Architecture of Singapore: history, styles, and urban development Architecture of Singapore
- Archive: collections of records, preservation, and access Archive
- Archivist: role, practices, history, and modern challenges Archivist
- Archivist of the United States
- Archon (Aisne) — a rural commune in northern France Archon, Aisne
- Archosaurs: evolution, key features, and Mesozoic dominance Archosaur
- Archosauromorphs: evolution, traits, and major groups Archosauromorph
- Archostemata: the primitive, basal suborder of beetles Archostemata
- Archuleta County, Colorado
- Archway tube station (London Underground) Archway tube station
- Archway, London — district and transport hub in Islington Archway, London
- Arcins — commune in Gironde, Nouvelle-Aquitaine, France Arcins
- Arcis-sur-Aube — commune in the Aube department, Grand Est, France Arcis-sur-Aube
- ARCNET (Attached Resource Computer Network): an early token‑passing LAN ARCNET
- ARCO (Atlantic Richfield Company): history, operations, and brand ARCO
- Arco, Idaho — history, geography and notable facts Arco, Idaho
- Arcola, Illinois
- Arconciel, Fribourg: French-speaking municipality in Sarine District, Switzerland Arconciel
- Arçonnay — a commune in Sarthe, Pays de la Loire, France Arçonnay
- Arconville: a rural commune in Aube, Grand Est, France Arconville
- Arcsecond: definition, notation, conversions and astronomical uses Arcsecond
- Arctic: geography, climate, ecosystems, and human significance Arctic
- Alaska Arctic Region: Geography, Communities, and Economy Arctic Alaska
- Arctic char (Salvelinus alpinus): biology, distribution, and conservation Arctic char
- Arctic Circle: definition, geography, phenomena, and changing boundary Arctic Circle
- Arctic Cordillera: Canada's Northern Mountain Chain Arctic Cordillera
- Arctic fox (Vulpes lagopus): appearance, adaptations and ecology Arctic fox
- Arctic hare (Lepus arcticus) Arctic hare
- Arctic Monkeys: English indie rock band from Sheffield Arctic Monkeys
- Arctic National Wildlife Refuge (ANWR): overview, wildlife, and controversy Arctic National Wildlife Refuge
- Arctic Ocean — geography, ecology, and human activity Arctic Ocean
- Arctic tern (Sterna paradisaea): migration, appearance, and range Arctic tern
- Arctic willow (Salix arctica) Arctic willow
- Arctiidae — tiger moths, lichen moths and woolly bears Arctiidae
- Arcturus (Alpha Boötis) — Bright Orange Giant Star Arcturus
- Arcy-Sainte-Restitue — commune in the Aisne department, northern France Arcy-Sainte-Restitue
- Arcy-sur-Cure
- ARD — German public broadcasting consortium ARD (broadcaster)
- Arda Turan
- Ardabil: historical city and cultural center in northwestern Iran Ardabil
- Ardabil Province, Iran Ardabil province
- Ardahan, city in northeastern Turkey Ardahan
- Ardakan — capital of Sepidan County in Fars Province, Iran Ardakan, Fars
- Ardara: small Sardinian town and comune in the Province of Sassari Ardara
- Ardashir I — Founder of the Sasanian Empire Ardashir I
- Ardauli: small inland comune in the Province of Oristano, Sardinia Ardauli
- Ardchyle — village in Stirling, Scotland Ardchyle
- Ardèche (department) — geography, history and highlights Ardèche
- Ardèche (river)
- Ardenay-sur-Mérize — a concise guide to the commune in Sarthe, France Ardenay-sur-Mérize
- Ardennes
- Ardennes (department)
- Ardennes (forest)
- Ardeonaig: small settlement on Loch Tay in central Scotland Ardeonaig
- Ardez — village in the Lower Engadine, Graubünden, Switzerland Ardez
- Ardhendu Bhushan Bardhan
- Ardico Magnini — Italian football defender (1928–2020) Ardico Magnini
- Ardingly: village in Mid Sussex, West Sussex Ardingly
- Ardipithecus: an early hominin genus and its significance Ardipithecus
- Ardleigh — village and civil parish in Tendring, Essex Ardleigh
- Ardmore, Alabama
- Ardmore, Oklahoma
- Ardoix, a commune in Ardèche, southern France Ardoix
- Ardon, Loiret — French commune in the Loire Valley area Ardon, Loiret
- Ardon (Valais, Switzerland) Ardon, Switzerland
- Ardooie (municipality in West Flanders, Belgium) Ardooie
- Ardres: a commune in Pas-de-Calais, northern France Ardres
- Arduino — open-source microcontroller platform Arduino
- Åre — Swedish mountain village and ski resort Åre
- Åre Municipality, Jämtland County, Sweden Åre Municipality
- Are We Done Yet? — 2007 family comedy film (sequel and remake) Are We Done Yet?
- Are We There Yet? (2005 film) Are We There Yet?
- Are You Smarter Than a 5th Grader? — format, history, and global versions Are You Smarter Than a 5th Grader?
- Area (mathematics) — measure of two-dimensional space Area
- Area 51: history, purpose, secrecy and cultural impact Area 51
- Area code 242 — telephone numbering for the Bahamas Area code 242
- Area code 246 — Barbados (NANP) Area code 246
- Area code 268 (Antigua and Barbuda) Area code 268
- Area code 307 — the telephone code for Wyoming Area code 307
- Area code 313 (Detroit, Michigan) Area code 313
- Area code 316 (Wichita, Kansas) Area code 316
- Area code 318 (northern and central Louisiana) Area code 318
- Area code 401: the telephone code for Rhode Island Area code 401
- Area code 620 — Southern Kansas telephone area code Area code 620
- Area code 649 — Turks and Caicos Islands (NANP) Area code 649
- Area code 701 — North Dakota's single telephone area code Area code 701
- Area code 710 — United States government (NANP non‑geographic code) Area code 710
- Area code 785 (northern Kansas) Area code 785
- Area code 802 — Vermont's statewide telephone prefix Area code 802
- Area code 808 — Hawaii Area code 808
- Area code 869 — Saint Kitts and Nevis telephone numbering Area code 869
- Area code 913 — northeastern Kansas (Kansas City area) Area code 913
- Area code 989 (northeastern Michigan) Area code 989
- Area codes 202 and 771 (Washington, D.C.) Area codes 202 and 771
- Telephone area codes in Germany (Vorwahl) Area codes in Germany
- Area of Outstanding Natural Beauty (AONB) Area of Outstanding Natural Beauty
- Arecibo Message (1974) Arecibo message
- Aredale, Iowa
- Aren (Pyrénées-Atlantiques commune) Aren
- Arena: design, history, uses and distinctions Arena
- Arena (web browser)
- Arena da Amazônia — football stadium in Manaus, Brazil Arena da Amazônia
- Arena da Baixada (Estádio Joaquim Américo Guimarães) Arena da Baixada
- Arena football: indoor, high‑scoring variant of American football Arena football
- Arena Football League (AFL): History, Rules, and Legacy Arena Football League
- Arena rock (stadium or corporate rock): definition, history and characteristics Arena rock
- Arena, Wisconsin
- ArenaBowl: Championship of Arena Football ArenaBowl
- Arenac County, Michigan
- Arenal Volcano National Park — Costa Rica's volcanic reserve Arenal Volcano National Park
- Arendal — coastal city and municipality in southern Norway Arendal
- Arendonk, municipality in the province of Antwerp, Belgium Arendonk
- Arenzville, Illinois
- Areopagitica — John Milton's 1644 Defense of Unlicensed Printing Areopagitica
- Arequipa — the White City of southern Peru Arequipa
- Arequipa Region (Peru) Arequipa Region
- Arès (Gironde) — coastal commune on Arcachon Bay, southwestern France Arès
- Ares — Greek god of war and violent conflict Ares
- Ares (DC Comics) — The God of War and Wonder Woman’s Adversary Ares (DC Comics)
- Ares (Marco Jaggi) — Swiss professional wrestler and trainer Ares (wrestler)
- Ares V: NASA's cancelled heavy-lift cargo launch vehicle Ares V
- Aressy — Commune in Pyrénées-Atlantiques, southwestern France Aressy
- Aretha Franklin — American singer, songwriter, and the 'Queen of Soul' Aretha Franklin
- Aretha Franklin discography
- Arette (commune in Pyrénées-Atlantiques) Arette
- Areuse — former municipality and village in Neuchâtel, Switzerland Areuse
- Areyonga (Utju): Pitjantjatjara community and history in central Northern Territory Areyonga, Northern Territory
- Arezzo — historic city and provincial capital in Tuscany, Italy Arezzo
- Arfeuilles: a commune in the Allier department of central France Arfeuilles
- Arg of Karim Khan (Arg-e Karim Khan) — Citadel in Shiraz Arg of Karim Khan
- Argagnon — commune in Pyrénées-Atlantiques, southwestern France Argagnon
- Argali (Ovis ammon): the wild mountain sheep of Central Asia Argali
- Arganchy — commune in Calvados, Normandy, France Arganchy
- Argançon: a small commune in the Aube department of France Argançon
- Argead dynasty: rulers of ancient Macedon and creators of a Hellenic empire Argead dynasty
- Argelès-Gazost — commune in Hautes-Pyrénées, Occitanie Argelès-Gazost
- Argeliers — commune in Aude, Occitanie, France Argeliers
- Argelos (Pyrénées-Atlantiques) Argelos, Pyrénées-Atlantiques
- Argemone (prickly poppy): description, distribution, uses and risks Argemone
- Argences (Calvados) — commune in Normandy, France Argences
- Argens-Minervois
- Argenta, Illinois
- Argentan, Orne — town in Lower Normandy Argentan
- Argentavis magnificens — the giant teratorn of the Miocene Argentavis magnificens
- Argentenay — a rural commune in Yonne, central France Argentenay
- Argenteuil — Suburban commune on the Seine near Paris Argenteuil
- Argenteuil-sur-Armançon (commune in Yonne, France) Argenteuil-sur-Armançon
- Argentina: geography, people, history, and culture Argentina
- Argentina at the 2018 Winter Paralympics
- Argentina at the Olympics: Participation, history and sporting strengths Argentina at the Olympics
- Argentina national football team (La Albiceleste) Argentina national football team
- Argentine Antarctica
- Argentine Chamber of Deputies
- Argentine Chamber of Phonograms and Videograms Producers (CAPIF) Argentine Chamber of Phonograms and Videograms Producers
- Argentine Declaration of Independence
- Argentine Grand Prix — history and legacy of the Buenos Aires Formula One race Argentine Grand Prix
- Argentine National Anthem (Himno Nacional Argentino) Argentine National Anthem
- Argentine National Museum of History
- Argentine peso (ARS): overview, history and contemporary use Argentine peso
- Argentine Primera División
- Argentine rock (Rock Nacional) Argentine rock
- Argentine Senate
- Argentinos Juniors
- Argentinosaurus — giant titanosaur of the Late Cretaceous Argentinosaurus
- Argenton-Notre-Dame — former commune in Mayenne, France Argenton-Notre-Dame
- Argentré (Mayenne) — Commune in Pays de la Loire, France Argentré
- Arges (Argeș): river, county, and other meanings Arges
- Argeș (river)
- Argeș County, Romania Argeș County
- Arget (commune in Pyrénées-Atlantiques, France) Arget
- Argetoaia — commune in Dolj County, Romania Argetoaia
- Arghakhanchi District, Nepal Arghakhanchi District
- Arghanj Khwa District, Badakhshan Province, Afghanistan Arghanj Khwa District
- Argis — commune in Ain, Auvergne-Rhône-Alpes Argis
- Argo (2012 film) Argo (2012 movie)
- Argo Navis — the ancient ship constellation (former) Argo Navis
- Argo, Alabama — town profile and overview Argo, Alabama
- Argœuves: a commune in the Somme, Hauts-de-France Argœuves
- Argolis
- Argon (Ar) — inert noble gas: properties, history and common uses Argon
- Argonaut
- Argonauta (paper nautiluses): pelagic octopods and their eggcases Argonauta
- Argonautica — epic poem by Apollonius of Rhodes Argonautica
- Argonia, Kansas: Small Town History and Significance Argonia, Kansas
- Argos: Ancient City of the Peloponnese and Regional Centre Argos
- Argostoli — capital town of Kefalonia, Greece Argostoli
- Argoules — commune in the Somme, Hauts-de-France Argoules
- Arguel (Somme) — small commune in Hauts-de-France, northern France Arguel, Somme
- Argument (reasoning and persuasion) Argument
- Argument from Authority (Appeal to Authority) Argument from authority
- Argument from design (teleological argument) Argument from design
- Argument from False Premises
- Argument from Ignorance (argumentum ad ignorantiam) Argument from ignorance
- Argument from Inconsistent Revelations
- Argument from Nonbelief (Divine Hiddenness) Argument from nonbelief
- Argument of periapsis
- Argumentum ad lazarum (appeal to poverty) Argumentum ad lazarum
- Argus (album)
- Argus As 014 pulsejet engine Argus As 014
- Argyle, Iowa — Unincorporated Community in Lee County Argyle, Iowa
- Argyle, Texas: Overview, History, and Community Profile Argyle, Texas
- Argyle, Wisconsin
- Argyll — historic county and coastal region of western Scotland Argyll
- Argyll and Bute: geography, history, administration and economy Argyll and Bute
- Arhansus — commune in Pyrénées-Atlantiques, France Arhansus
- Arhat (arahant): Enlightened practitioner in Buddhism Arhat
- Ari Behn: Norwegian writer and public figure (1972–2019) Ari Behn
- Ari Rath: Austrian‑Israeli Journalist and Editor Ari Rath
- Aria (musical form) Aria
- ARIA Charts: Australia's Official Music Popularity Rankings ARIA Charts
- ARIA Hall of Fame
- Ariadne: helper of Theseus, consort of Dionysus Ariadne
- Ariajasuru Hasegawa
- Ariana Grande: Singer, Actress, and Cultural Figure Ariana Grande
- Arianism: early Christian teaching on Christ's nature Arianism
- Arianna Huffington: Greek‑American Author and Digital Media Pioneer Arianna Huffington
- Arianne Caoili: Filipino–Australian Chess Master and Olympiad Competitor Arianne Caoili
- Ariano Suassuna: Brazilian playwright, novelist and champion of Northeastern culture Ariano Suassuna
- Arica — Chilean port city and regional capital Arica
- Arica Province, Chile — geography, history, administration and economy Arica Province
- Arica y Parinacota Region (XV), northern Chile Arica y Parinacota Region
- Aridaia — town in Pella, Central Macedonia, Greece Aridaia
- Arie den Hartog — Dutch Classic Road Racing Champion Arie den Hartog
- Arie Irawan — Malaysian Professional Golfer Arie Irawan
- Ariège (department, Occitanie, France) Ariège (department)
- Ariège (river)
- Arieh Warshel — Computational Chemist and Nobel Laureate Arieh Warshel
- Ariel (1988 film) Ariel
- Ariel (moon) — an icy, geologically varied satellite of Uranus Ariel (moon)
- Ariel Castro kidnappings — Cleveland missing trio (2002–2013) Ariel Castro kidnappings
- Ariel Ibagaza — Argentine attacking midfielder Ariel Ibagaza
- Ariel Lin (Lin Yichen) — Taiwanese actress and singer Ariel Lin
- Ariel Nogueira
- Ariel Ortega
- Ariel Sharon
- Ariel Sharon Park (Ayalon Park) — reclaimed urban park in the Tel Aviv area Ariel Sharon Park
- Ariel University
- Ariel Winter
- Aries: constellation and astrological sign Aries
- Aries (constellation)
- Aries Spears
- Arif Alvi — President of Pakistan and founding PTI politician Arif Alvi
- Arif Dirlik: Historian of Modern China, Globalization, and Postcolonial Critique Arif Dirlik
- Arif Malikov — Azerbaijani composer of ballet and orchestral music Arif Malikov
- Arik Einstein: Israeli singer, actor and cultural figure Arik Einstein
- Arika Yumemiya — protagonist of My-Otome Arika Yumemiya
- Arimo, Idaho
- Ariodante — Handel's three‑act opera based on Orlando Furioso Ariodante
- Arion, Iowa
- Arirang: The Korean Folk Song and Cultural Symbol Arirang
- Arirang (2011 film) Arirang (2011 movie)
- Aris Thessaloniki F.C.
- Arisaka rifle
- Arisdorf — municipality in Basel-Landschaft, Switzerland Arisdorf
- Arispe, Iowa — a small rural city Arispe, Iowa
- Arista Records: American record label and imprint of Sony Music Arista Records
- Aristarchus of Samos: Ancient Proponent of a Sun‑Centered Cosmos Aristarchus of Samos
- Aristarkh Lentulov: Russian Avant‑Garde Painter and Stage Designer Aristarkh Lentulov
- Aristau — municipality in the district of Muri, Aargau, Switzerland Aristau
- Aristide Briand: French statesman, peacemaker, and Nobel laureate Aristide Briand
- Aristide Cavaillé-Coll: Innovator of the Romantic Organ Aristide Cavaillé-Coll
- Aristide von Bienefeldt — Dutch novelist and LGBT writer Aristide von Bienefeldt
- Aristides Pereira
- Aristides Royo — President of Panama (1978–1982) Aristides Royo
- Aristocracy: definition, history, types, and modern legacy Aristocracy
- Aristocrat: history, roles, and social significance Aristocrat
- Aristolochia — birthworts and pipevines (Aristolochiaceae) Aristolochia
- Aristolochiaceae (Birthwort or Pipevine Family) Aristolochiaceae
- Aristophanes: Playwright of Ancient Greek Old Comedy Aristophanes
- Aristotle (384–322 BC) Aristotle
- Aristotle Onassis
- Arita, Saga: Japan's historic center of porcelain production Arita, Saga
- Aritatsu Ogi
- Arithmetic: fundamentals, operations, history, education, and applications Arithmetic
- Arithmetic Logic Unit (ALU) Arithmetic logic unit
- Arithmetic precision: definitions, representation, rounding, and practical use Arithmetic precision
- Ariton, Alabama
- Arity (number of arguments of a function) Arity
- Aritzo — Mountain town in the Province of Nuoro, Sardinia, Italy Aritzo
- Arius (c. 260–336): Early Christian Theologian and the Arian Controversy Arius
- Ariwara no Narihira
- Ariyalur: Limestone town and district headquarters in Tamil Nadu Ariyalur
- Ariyalur district
- Ariyalur taluk
- Arizona: Geography, history, and significance of the Grand Canyon State Arizona
- Arizona (1931 film) Arizona (movie)
- Arizona Cardinals
- Arizona Coyotes