15-letter words containing a, c, t, i
- adenoidectomies — Plural form of adenoidectomy.
- adhesive factor — the ratio of the force that can be exerted on driving wheels with full traction to the weight on the driving wheels, usually expressed as a percentage.
- adiabatic chart — a graph for the analysis of adiabatic processes.
- adjective group — An adjective group or adjectival group is a group of words based on an adjective, such as 'very nice' or 'interested in football'. An adjective group can also consist simply of an adjective.
- adjectivization — Grammar. to make into an adjective, as by adding a suffix: The noun mirth can be adjectivized by adding -ful or -less to form the adjectives mirthful and mirthless.
- admiralty cloth — melton cloth, used for coats and jackets, especially for the naval service.
- admiralty court — the court that has jurisdiction in matters relating to maritime law
- adoption agency — an agency that matches children needing adoption with people willing to adopt
- adrenalectomies — Plural form of adrenalectomy.
- adult education — Adult education is education for adults in a variety of subjects, most of which are practical, not academic. Classes are often held in the evenings.
- advanced credit — credit toward a degree allowed to a student by a college for courses taken elsewhere or for high scores on preliminary examinations
- aegyptopithecus — a genus of extinct anthropoid ape of the Oligocene Period known from remains found in Egypt.
- aerodynamicists — Plural form of aerodynamicist.
- agranulocytosis — a serious and sometimes fatal illness characterized by a marked reduction of leucocytes, usually caused by hypersensitivity to certain drugs
- agriculturalist — An agriculturalist is someone who is an expert on agriculture and who advises farmers.
- air conditioned — If a room or vehicle is air conditioned, the air in it is kept cool and dry by means of a special machine.
- air conditioner — An air conditioner is a machine which keeps the air in a building cool and dry.
- airborne attack — an attack involving airborne troops
- airconditioning — Alternative spelling of air conditioning.
- aircraft hangar — a large workshop or building for storing and maintaining aircraft
- airmail sticker — a sticker that is put on airmail letters to make sure they are not sent by surface mail
- akinetic mutism — a state of apparent alertness with normal eye movements but no speech or other voluntary motion, usually due to a stroke.
- alberta clipper — (in Canada) an area of low pressure that forms in winter near the Rocky Mountains
- algorithmically — Using an algorithm.
- alignment chart — nomogram.
- allorecognition — The ability of an individual organism to distinguish its own tissues from those of another.
- allotriomorphic — (of minerals) not having their own regular shape (as determined by their internal structure) but being shaped instead by adjacent minerals
- alopecia areata — loss of hair in circumscribed patches.
- alpine accentor — a small bird of the sparrow family, Prunella collaris, found especially in mountain regions of S Europe and Asia
- alta california — a former Spanish colony of New Spain, in the modern-day states of California, Nevada, and N Arizona: ceded by Mexico to the United States 1848.
- aluminosilicate — a silicate in which some of the silicon in the tetrahedral unit SiO4 has been replaced by aluminium
- ambisyllabicity — (poetry) The property of a consonant being analysed as acting simultaneously as the coda of one syllable and the onset of the following syllable.
- ambrosian chant — the liturgical chant, established by Saint Ambrose, characterized by ornamented, often antiphonal, singing.
- ambulance train — a train designed to carry sick or injured people
- amegakaryocytic — Characterized by a lack of megakaryocytes.
- amenity society — a voluntary society established with the purpose of preserving historic art and architecture
- america firster — a member or supporter of the America First Committee.
- american beauty — a variety of hybrid, perennial red rose
- american blight — any plant louse of the family Aphididae, characterized by a waxy secretion that appears like a jumbled mass of fine, curly, white cottony or woolly threads, as Eriosoma lanigerum (woolly apple aphid or American blight) and Prociphilus tessellatus (woolly alder aphid)
- american cotton — upland cotton.
- american gothic — a painting (1930) by Grant Wood.
- american marten — pine marten (def 2).
- american smooth — a style of competitive ballroom dancing which incorporates elements of Latin dance
- americanization — Americanization is the process by which people or countries become more and more similar to Americans and the United States.
- americanologist — a foreign expert or specialist in American cultural or political matters: a leading Americanologist in the Kremlin.
- ammunition clip — a device for storing rounds of ammunition and feeding them into a weapon
- amphitheatrical — Having some of the characteristics of an amphitheatre.
- anacoluthically — in an anacoluthic manner
- anacostia river — a river in the District of Columbia flowing into the Potomac River. about 24 miles (39 km) long.
- anaesthetically — by means of an anaesthetic