12-letter words containing a, c, t, i, o
- appreciatory — appreciative.
- apricot tart — a pastry case filled with apricots
- archaization — Process of becoming or turning something more archaic.
- archegoniate — having archegonia
- archeologist — archaeology.
- archibenthos — the ocean bottom between the littoral and abyssal zones: from depths of approximately 200 feet (60 meters) to 3300 feet (1000 meters).
- arctic ocean — the ocean surrounding the North Pole, north of the Arctic Circle. Area: about 14 100 000 sq km (5 440 000 sq miles)
- arctophilist — a collector of teddy bears
- aristocratic — Aristocratic means belonging to or typical of the aristocracy.
- aristolochia — any of various plants of the genus Aristolochia of the family Aristolochiaceae
- aristophanic — 448?–385? b.c, Athenian comic dramatist.
- aromatically — having an aroma; fragrant or sweet-scented; odoriferous.
- art director — a person responsible for the sets and costumes in a film
- arthropathic — disease of the joints.
- arthroscopic — the use of an arthroscope to diagnose an injury to or disease of a joint or to perform minor surgery on a joint.
- articulation — Articulation is the action of producing a sound or word clearly, in speech or music.
- articulators — Plural form of articulator.
- articulatory — an act or the process of articulating: the articulation of a form; the articulation of a new thought.
- artiodactyle — (zoology) One of the Artiodactyla, a group of ungulates.
- artiodactyls — Plural form of artiodactyl.
- arts council — an organization that provides funding for a variety of arts activities
- ascensionist — a person who has completed a mountain ascent, esp a notable one
- aspect ratio — the ratio of width to height of the picture on a television or cinema screen
- associations — Plural form of association.
- assuefaction — the condition of being or becoming familiar with or used to something
- astacologist — a person who investigates and analyses crayfish
- astigmoscope — astigmatoscope.
- astrochemist — (chemistry, astronomy) A chemist or astronomer whose speciality is astrochemistry.
- astrodynamic — Pertaining to astrodynamics.
- astrological — the study that assumes and attempts to interpret the influence of the heavenly bodies on human affairs.
- astronautics — the science and technology of space flight
- astronomical — If you describe an amount, especially the cost of something as astronomical, you are emphasizing that it is very large indeed.
- astrophysics — Astrophysics is the study of the physical and chemical structure of the stars, planets, and other natural objects in space.
- asymptomatic — If someone with a disease is asymptomatic, it means that they do not show any symptoms of the disease.
- asymptotical — of or relating to an asymptote.
- atactostelic — Of or possessing an atactostele.
- atheological — having an aversion or resistance to theology
- atheoretical — having no connection with and not founded on theory
- athrocytosis — the capability of a cell to receive and store matter
- atmospherics — Atmospherics are elements in something such as a piece of music or a book which create a certain atmosphere.
- atomic clock — an extremely accurate clock in which an electrical oscillator is controlled by the natural vibrations of an atomic or molecular system such as caesium or ammonia
- atomic power — nuclear power.
- atychiphobia — (rare) The fear of failure.
- au contraire — on the contrary
- auction room — a room in a building where auctions take place
- auction sale — an instance of items being sold by auction
- auction site — a commercial website on which items are sold by internet auction
- auctioneered — Simple past tense and past participle of auctioneer.
- auscultation — the diagnostic technique in medicine of listening to the various internal sounds made by the body, usually with the aid of a stethoscope
- autochthonic — pertaining to autochthons; aboriginal; indigenous (opposed to heterochthonous).