| Arrhenatherum rupestre | Arrhenatherum scabrinsculum | Arrhenatherum scabrum |
| Arrhenatherum submuticum | Arrhenatherum sylvaticum | Arrhenia lobata |
| Arrhenius equation | Arrhenius plot | Arrhythmia |
| Arrhythmogenic right ventricular dysplasia | Arrian | Arriba, Colorado |
| Arrietty | Arrigo Sacchi | Arrondissement |
| Arrondissements of France | Arrow | Arrow (Israeli missile) |
| Arrow (TV series) | Arrow 3 | Arrow Emblem: Hawk of the Grand Prix |
| Arrow of time | Arrow Point, Missouri | Arrow Rock, Missouri |
| Arrow Sport | Arrowsmith (film) | Arrowsmith, Illinois |
| Arroyomolinos | ARS | Arsanilic acid |
| Arsène Lupin | Arsène Wenger | Arsen Avetisyan |
| Arsenal F.C. | Arsenic | Arsenic acid |
| Arsenic contamination of groundwater | Arsenic pentachloride | Arsenic pentoxide |
| Arsenic tribromide | Arsenic trichloride | Arsenic triiodide |
| Arsenic trioxide | Arsenic triselenide | Arsenic trisulfide |
| Arsenic(III) chloride | Arsenic(V) oxide | Arsenide |
| Arsenopyrite | Arsenous acid | Arshad al-Umari |
| Arshad Warsi | Arshaq Sharqi Rural District | Arshaq-e Sharqi Rural District |
| Arsine | Arsole | Arson |
| Arsphenamine | ART | Art |
| ART america | Art Attack | Art Carney |
| Art Deco | ART Europe | ART europe |
| Art Gallery of Ontario | Art Infusion | Art Malik |
| Art Nouveau | Art Parkinson | ART Teenz |
| Art therapy | Art world | ART افلام |
| Art الليث | ART المفتوحة | ART الموسيقى |
| ART المنوعات | ART المناهج | ART المناسبات |
| ART الحكايات | ART الطرب | ART العالمية |
| ART سينما | Art سبورت | ART سبورت (الرياضية) |
| ART عين | Artamus | Artas, South Dakota |
| Artaxerxes I of Persia | Artémidore | ArtCyclopedia |
| Artem Mikoyan | Artem Milevskiy | Artemia |
| Artemidorus | Artemis | Artemisia |
| Artemisia absinthium | Artemisia annua | Artemisia atrata |
| Artemisia campestris | Artemisia dracunculus | Artemisia genipi |
| Artemisia Gentileschi | Artemisia glacialis | Artemisia herba-alba |
| Artemisia judaica | Artemisia lactiflora | Artemisia ludoviciana |
| Artemisia maritima | Artemisia pontica | Artemisia stelleriana |
| Artemisinin | Artemotil | Arterial arcades |
| Arterial blood | Arterial blood gas | Arterial catheter |
| Arterial hypertension | Arterial resistivity index | Arterial tree |
| Arteries | Arteriole | Arteriosclerosis |
| Arteriovenous fistula | Arteriovenous malformation | Arteriviridae |
| Arterivirus | Artery | Artery of bulb of penis |
| Artery of bulb of vestibule | Artery of round ligament of uterus | Artery to the ductus deferens |
| Artesia, Mississippi | Artesian aquifer | Artesian, South Dakota |
| Artesunate | Artesunate/amodiaquine | Arthralgia |
| Arthritis | Arthritis mutilans | Arthrodermataceae |
| Arthrodesis | Arthrogrryposis | Arthrogryposis |
| Arthrology | Arthropod | Arthropoda |
| Arthroscopy | Arthur (1981 film) | Arthur Aaron (footballer) |
| Arthur Andersen | Arthur Ashe | Arthur Balfour |
| Arthur Bernardes (football manager) | Arthur Bisguier | Arthur Boka |
| Arthur C. Clarke | Arthur C. Clarke Award | Arthur Casagrande |
| Arthur Cayley | Arthur Compton | Arthur Conan Doyle |
| Arthur Cox (footballer) | Arthur Cronquist | Arthur de Gobineau |
| Arthur Demarest | Arthur Dimmesdale | Arthur Eddington |
| Arthur Eichengrün | Arthur Evans | Arthur Golden |
| Arthur Harden | Arthur Hays Sulzberger | Arthur Henderson |
| Arthur Henry Reginald Buller | Arthur Holmes | Arthur Honegger |
| Arthur Huber-Morath | Arthur J. Arberry | Arthur Jaffe |
| Arthur Jeffery | Arthur john arberry | Arthur John Arberry |
| Arthur Johnson (manager) | Arthur Kingsley Porter | Arthur Koestler |
| Arthur Kornberg | Arthur Laffer | Arthur Leonard Schawlow |
| Arthur Miller | Arthur Numan | Arthur Ponsonby, 1st Baron Ponsonby of Shulbrede |
| Arthur Q. Bryan | Arthur Ravenel Jr. Bridge | Arthur Rimbaud |
| Arthur Rubinstein | Arthur Ruppin | Arthur Scherbius |
| Arthur Schmidt (film editor) | Arthur Schnitzler | Arthur Schopenhauer |
| Arthur Schuster | Arthur Seyss-Inquart | Arthur Stanley Eddington |
| Arthur Stanley Tritton | Arthur Surridge Hunt | Arthur Tansley |
| Arthur Township, Michigan | Arthur Waskow | Arthur Wellesley, 1st Duke of Wellington |
| Arthur Whitten Brown | Arthur William Hill | Arthur Wynne |
| Arthur, Illinois | Arthur, Iowa | Arthur, Nebraska |
| Arthur, North Dakota | Arthur, Wisconsin | Arthus reaction |
| Artibeus jamaicensis | Article (publishing) | Article 301 (Turkish Penal Code) |
| Article 9 of the Japanese Constitution | Articular capsule | Articular capsule of the knee joint |
| Articular disk | Articulated robot | Artificial bone |
| Artificial brain | Artificial cardiac pacemaker | Artificial consciousness |
| Artificial demand | Artificial flower | Artificial gene synthesis |
| Artificial heart | Artificial induction of immunity | Artificial insemination |
| Artificial intelligence | Artificial island | Artificial kidney |
| Artificial language | Artificial life | Artificial limb |
| Artificial lung | Artificial neural network | Artificial organ |
| Artificial reef | Artificial seawater | Artificial skin |
| Artificial urinary bladder | Artificial uterus | Artificial vagina |
| Artificially Expanded Genetic Information System | Artillery | Artillery battery |
| Artillery fuze | Artinskian | Artiocetus |
| Artiodactyla | Artisan | Artistic |
| Artistic License | Artistic rendering | Artjoms Rudņevs |
| Arto Javanainen | Arto Paasilinna | Arto Saari |
| Artocarpeae | Artocarpus | Artocarpus altilis |
| Artocarpus heterophyllus | Artocarpus thailandicus | Artolsheim |
| ARTPOP | Artpop | ArtRave: The Artpop Ball |
| Artroeite | Arts and Crafts movement | Arts and Humanities Data Service |
| Arts and Humanities Research Council | Artsem Karalek | Artturi Ilmari Virtanen |
| Artur Avila | Artur Balder | Artur Boruc |
| Artur Geworkýan | Artur Jorge (footballer) | Artur Lundkvist |
| Artur Moraes | Artur Phleps | Artur Sobiech |
| Artur Wichniarek | Arturo Coddou | Arturo Fernández Meyzán |
| Arturo Ithurralde | Arturo Norambuena | Arturo Ricci |
