12-letter words containing r, u
- arbitrageurs — Plural form of arbitrageur.
- arc spectrum — a spectrum formed from the light produced by an electric arc, characteristic of the gas or vapor through which the arc passes.
- arch support — a rigid support placed inside a shoe so that its molded form fits the arch of the foot and relieves strain on the muscles of the foot while walking, standing, etc.
- arched truss — a truss having an archlike form but unlike a true arch in that it is free to move horizontally at its base, as in expanding or contracting because of temperature changes.
- archesporium — archespore.
- archipallium — (anatomy) The oldest region of the brain's pallium, often considered contiguous with the olfactory cortex, but varying among species. In humans, the archipallium makes up the hippocampus.
- architecture — Architecture is the art of planning, designing, and constructing buildings.
- archosaurian — belonging to or characteristic of the archosaurs
- arenaviruses — Plural form of arenavirus.
- argillaceous — (of sedimentary rocks and deposits) composed of very fine-grained material, such as clay, shale, etc
- armour plate — a tough heavy steel, usually containing chromium, nickel, and molybdenum and often hardened on the surface, used for protecting warships, tanks, etc
- armourbearer — One who carries armor for another.
- armoured car — a fast lightly armed and armoured vehicle, mainly used for reconnaissance
- army cutworm — the larva of a noctuid moth, Chorizagrotis auxiliaris, that is a pest of wheat and alfalfa in the Plains states.
- army surplus — used or unused articles of military clothing, equipment, etc previously allocated to or intended for the use of army personnel but now sold off to members of the public
- around about — Around about means approximately.
- arousability — to stimulate sexually.
- arquebusiers — harquebusier.
- arseniferous — Lb geology Containing or producing arsenic.
- arseniureted — combined with arsenic
- arseno group — the bivalent group −As=As−.
- arsino group — the univalent group H 2 As−.
- arthur evans — Sir Arthur John, 1851–1941, English archaeologist.
- articulately — uttered clearly in distinct syllables.
- articulating — Present participle of articulate.
- articulation — Articulation is the action of producing a sound or word clearly, in speech or music.
- articulative — relating to articulation
- articulators — Plural form of articulator.
- articulatory — an act or the process of articulating: the articulation of a form; the articulation of a new thought.
- arts council — an organization that provides funding for a variety of arts activities
- arts student — a person studying an arts subject
- as per usual — as usual
- ash-coloured — silver-grey in colour
- ashurbanipal — died ?626 bc, king of Assyria (?668–?626): son of Esarhaddon. He built the magnificent palace and library at Nineveh
- assurbanipal — Ashurbanipal
- astronautics — the science and technology of space flight
- astrotourist — a person who pays to travel into space as a form of recreation
- astroturfing — a PR tactic used in politics and advertising in which actors are paid to display overt and apparently spontaneous grassroots support for a particular product, policy, or event
- asynchronous — An asynchronous electric machine is one in which the magnetic field and the rotation are not exactly the same.
- at a premium — If something is at a premium, it is wanted or needed, but is difficult to get or achieve.
- at a venture — at random; by chance
- at all hours — If you say that something happens at all hours of the day or night, you disapprove of it happening at the time that it does or as often as it does.
- atheromatous — a sebaceous cyst.
- atmospherium — an optical system used to simulate images of atmospheric phenomena, as cloud formations, storms, and day and night, on the inside of a dome.
- attenborough — Sir David. born 1926, British naturalist and broadcaster; noted esp for his TV series Life on Earth (1978), The Living Planet (1983), The Life of Birds (1998), The Life of Mammals (2002), and First Life (2010)
- attributable — If something is attributable to an event, situation, or person, it is likely that it was caused by that event, situation or person.
- attributions — Plural form of attribution.
- au contraire — on the contrary
- auction room — a room in a building where auctions take place
- auctioneered — Simple past tense and past participle of auctioneer.