519,064 articles
Auxiliary power unit
An auxiliary power unit (APU) is a small gas turbine, usually in an airliner's tail, that supplies power and air when the main engines are off and starts them.
Auxiliary Territorial Service
Auxiliary Territorial Service (ATS), the women's branch of the British Army, formed September 1938 and absorbed into the Women's Royal Army Corps in 1949; about 250,000 women served, including anti-aircraft crews who could not fire the guns.
Auxiliary verb
Auxiliary verb (helping verb): a verb used with a main verb to express tense, aspect, mood, voice, or polarity. English auxiliaries are be, do, have plus modals like can, may, must, will; they invert with subjects and resist inflection.
Auxiliary-field quantum Monte Carlo for solids
Auxiliary-field quantum Monte Carlo (AFQMC) is a projector quantum Monte Carlo method computing ground-state properties of correlated many-electron systems and periodic solids, developed in phaseless form by Shiwei Zhang and Henry Krakauer.
Auxilo Finserve
Auxilo Finserve Private Limited, formerly Stellenyak General Finance Private Limited, is a Mumbai-headquartered education finance NBFC in India, lending to students studying in India and abroad and to educational institutions.
Auxin
Auxin (IAA, indole-3-acetic acid) is the principal plant hormone, coordinating growth via gradients formed by TAA/YUCCA biosynthesis, PIN/AUX1 polar transport, and TIR1/AFB-Aux/IAA-ARF signaling; used as rooting hormones and 2,4-D herbicides.
Auxin Efflux Carrier
Auxin efflux carrier: membrane protein exporting the plant hormone auxin (IAA) from cells, chiefly the PIN-FORMED (PIN) family plus ABCB pumps; PINs are homodimeric elevator-type transporters inhibited by NPA.
Auxin response factor
Auxin response factors (ARFs) are plant-specific B3-family transcription factors, the final effectors of the nuclear auxin pathway, binding AuxREs and regulated by Aux/IAA repressors; classes A, B, C; first cloned 1997.
Auxin-binding protein
Auxin-binding protein 1 (ABP1) is a 22 kDa cupin plant protein, discovered in maize in 1972, that binds auxin at apoplastic pH and acts with TMK kinases as a cell-surface auxin co-receptor, distinct from nuclear TIR1/AFB receptors.
Auxis rochei
Auxis rochei, the bullet tuna (basionym Scomber rochei Risso, 1810), is a small neritic Scombridae tuna of the Atlantic, Indian, and western Pacific Oceans including the Mediterranean; IUCN Least Concern globally but critically overfished in the central Mediterranean.
Auxis thazard
Auxis thazard, frigate tuna or frigate mackerel, is a small scombrid tuna (Scombridae, Thunnini) of tropical and subtropical seas; distinguished from bullet tuna A. rochei by oblique wavy back markings, fished commercially, IUCN Least Concern.
Auxo Dorsum
Auxo Dorsum is an 82 km ridge (dorsum) in southern Argyre Planitia, Mars, at 55.72 S, 318.24 E; IAU-approved 1991, named for one of the Graces, and interpreted as a lava tube rather than an esker.
Auzaar (औज़ार)
Auzaar (औज़ार, "The Weapon") is a 1997 Hindi action thriller, Sohail Khan's directorial debut, starring Salman Khan, Sanjay Kapoor, and Shilpa Shetty; Tips Films' first solo production, with music by Anu Malik.
AV
AV (青春夢工場) is a 2005 Hong Kong comedy-drama-romance directed by Pang Ho-Cheung, about four students who take an entrepreneur loan to hire Japanese AV actress Manami Amamiya for a fake film.
AV Alta FC
AV Alta FC is a USL League One professional soccer club in Lancaster, California (Antelope Valley), founded by John Smelzer, playing at the 5,300-seat Lancaster Municipal Stadium since March 2025.
Av HaRachamim
Av HaRachamim (אב הרחמים, Father of Mercy) is an Ashkenazi Jewish memorial prayer recited on Shabbat morning after the Torah reading, composed in memory of communities killed in the Crusades.
AV idol
AV idol (AV女優): a performer in Japan's adult video industry marketed with idol-style branding and fan events. Distinct from non-nude gravure idols; tantai and kikaku production styles; regulated by Article 175 and the 2022 performer-protection law.
AV nodal reentrant tachycardia
AV nodal reentrant tachycardia (AVNRT), the most common paroxysmal supraventricular tachycardia, is a reentrant arrhythmia of the AV node based on dual fast and slow pathway physiology, treated acutely with vagal maneuvers and adenosine and cured by slow-pathway catheter ablation.
AV1
AV1 (AOMedia Video 1) is an open, royalty-free video compression format developed by the Alliance for Open Media and published in 2018, offering about 30% better compression than VP9.
AV2
AV2 (AOMedia Video 2) is a royalty-free video coding specification published by the Alliance for Open Media, finalized in May 2026 to match AV1's quality at roughly 30% lower bitrate.
AV3Sb5
AV3Sb5 kagome superconductors are layered vanadium kagome metals with A = K, Rb, or Cs that superconduct below about 3 K and form a charge density wave near 80 to 100 K.
Ava (2020 film)
Ava (2020) is an American action thriller directed by Tate Taylor, written by Matthew Newton, starring Jessica Chastain as a black-ops assassin marked for death by her own organization; released by Vertical Entertainment on September 25, 2020, distinct from the 2017 French and Iranian films of the same name.
Ava (wrestler)
Ava (Simone Johnson, born 2001), daughter of The Rock, is an American wrestling personality; first fourth-generation WWE signee (2020), Schism member, and NXT General Manager from January 2024 until leaving WWE in January 2026.
AVA Airlines
AVA Airlines (Persian: هواپیمایی آوا) is a privately held Iranian passenger airline based at Tehran Mehrabad Airport. Founded in 2023, it flies domestic routes plus international services to Istanbul, Baghdad, and Kabul.
Ava Alice Muriel Astor
Ava Alice Muriel Astor (1902–1956) was an American heiress and daughter of John Jacob Astor IV, who left her a $5 million trust after he died in the 1912 Titanic sinking.
Ava DuVernay
Ava DuVernay, American filmmaker from Long Beach, California, director of Selma, 13th, A Wrinkle in Time, and When They See Us; first Black woman Golden Globe Best Director nominee and founder of the ARRAY collective.
Ava Gardner
Ava Gardner (1922–1990), American film star from rural North Carolina, broke through as Kitty Collins in The Killers (1946), earned an Oscar nomination for Mogambo, married Rooney, Shaw, and Sinatra, and lived in Spain and London.
Ava Kingdom
The Ava Kingdom (Inwa) was the dominant Upper Burmese kingdom of 1364 to 1555, founded by Thadominbya at Ava and ended when King Bayinnaung of Toungoo conquered it in 1555.
Ava Lowle Willing
Ava Lowle Willing (1868-1958), later Baroness Ribblesdale, American socialite, first wife of John Jacob Astor IV, mother of Vincent Astor; divorced 1910, remarried Thomas Lister 1919.
Ava Max
Ava Max, born Amanda Ava Koci, is an American pop singer of Albanian descent whose 2018 single "Sweet but Psycho" topped charts worldwide, and who has released three studio albums.