18-letter words containing a, d, n, t, i, o
- radiation sickness — sickness caused by irradiation with x-rays or other nuclear radiation as a result of therapeutic treatment, accidental exposure, or a nuclear bomb explosion and characterized by nausea, vomiting, headache, cramps, diarrhea, loss of hair and teeth, destruction of white blood cells, and prolonged hemorrhage.
- radioactive dating — any method of determining the age of earth materials or objects of organic origin based on measurement of either short-lived radioactive elements or the amount of a long-lived radioactive element plus its decay product.
- radiocarbon dating — the determination of the age of objects of organic origin by measurement of the radioactivity of their carbon content.
- radiocommunication — communication by means of radio waves
- radiometric dating — any method of determining the age of earth materials or objects of organic origin based on measurement of either short-lived radioactive elements or the amount of a long-lived radioactive element plus its decay product.
- radius of gyration — the distance from an axis at which the mass of a body may be assumed to be concentrated and at which the moment of inertia will be equal to the moment of inertia of the actual mass about the axis, equal to the square root of the quotient of the moment of inertia and the mass.
- ragtag and bobtail — the riffraff; rabble: The ragtag and bobtail of every nation poured into the frontier in search of gold.
- rain cats and dogs — water that is condensed from the aqueous vapor in the atmosphere and falls to earth in drops more than 1/50 inch (0.5 mm) in diameter. Compare drizzle (def 6).
- rapid eye movement — rapidly shifting, continuous movements of the eyes beneath closed lids during the stage of sleep characterized by dreaming.
- reduction strategy — (theory) An algorithm for deciding which redex(es) to reduce next. Different strategies have different termination properties in the presence of recursive functions or values. See string reduction, normal order reduction, applicative order reduction, parallel reduction
- registered company — a company which has officially registered its business
- reinforced plastic — plastic with fibrous matter, such as carbon fibre, embedded in it to confer additional strength
- report an accident — If you report an accident, you inform an insurer or the police or other authorities that an accident has occurred.
- rescind a contract — If an insurer rescinds an insurance contract, it terminates it because facts have been concealed or misrepresented by the proposer.
- residential school — (in Canada) a boarding school maintained by the Canadian government for Indian and Inuit children from sparsely populated settlements
- restoration comedy — English comedy of the period of the Restoration, stressing manners and social satire.
- restraint of trade — action tending to interrupt the free flow of goods and services, as by price fixing and other practices that have the effect of reducing competition.
- retrograde amnesia — a memory disorder characterized by an inability to remember events or experiences that occurred before a significant point in time.
- rhode island white — one of a dual-purpose American breed of chickens having white feathers and a rose comb.
- rhyming dictionary — a specialist dictionary organized by the final sounds of words, used to write poetry
- rotational molding — a method for molding hollow plastic objects by placing finely divided particles in a hollow mold that is rotated about two axes, exposing it to heat and then to cold.
- russian federation — a republic extending from E Europe to N and W Asia. 6,593,000 sq. mi. (17,076,000 sq. km). Capital: Moscow.
- saint george's day — April 23, celebrated in parts of the British Commonwealth in honor of the patron saint of Britain and especially in New Zealand as a bank holiday.
- saint john's bread — carob (def 2).
- saturated solution — A saturated solution is a solution in which there is so much solute that if there was any more, it would not dissolve.
- say/kiss goodnight — If you say goodnight to someone or kiss them goodnight, you say something such as 'Goodnight' to them or kiss them before one of you goes home or goes to sleep.
- science dictionary — a specialized dictionary covering terms in the life, earth, and physical sciences, such as the online Science Dictionary on Dictionary.com. A science dictionary includes many technical terms with precise, specialized meanings—terms not normally found in general dictionaries—making it an invaluable resource for students and professionals in scientific fields.
- scissors-and-paste — designating or of a piece of writing that has been assembled from a variety of sources rather than by original research, often in a hasty or uninspired way
- second triumvirate — the coalition and joint rule of the Roman Empire by Antony, Lepidus, and Octavian, begun in 43 bc
- secondary industry — manufacturing, services, etc.
- sedimentation tank — a tank into which sewage is passed to allow suspended solid matter to separate out
- self-contradiction — an act or instance of contradicting oneself or itself.
- self-contradictory — an act or instance of contradicting oneself or itself.
- self-determination — determination by oneself or itself, without outside influence.
- sex discrimination — the practice of treating male and female people unequally
- sign of the zodiac — one of the twelve constellations along the path of the ecliptic.
- sindbad the sailor — (in The Arabian Nights' Entertainments), a wealthy citizen of Baghdad who relates the adventures of his seven wonderful voyages.
- sit on one's hands — the terminal, prehensile part of the upper limb in humans and other primates, consisting of the wrist, metacarpal area, fingers, and thumb.
- skin friction drag — aerodynamic resistance or drag due to the contact of moving air with the surface of an airplane, a glider, etc.
- small outline dimm — (storage) (SO-DIMM) A smaller kind of DIMM with 72 pins (supporting 32-bit transfers) or 144 pins (64-bit transfers). Regular DIMMs have 168 pins and support 64-bit transfers. Being roughly half the size of the regular DIMM, SO-DIMMs are often used in notebook computers.
- sodium bicarbonate — a white, crystalline, water-soluble solid, in powder or granules, NaHCO 3 , usually prepared by the reaction of soda ash with carbon dioxide or obtained from the intermediate product of the Solvay process by purification: used chiefly in the manufacture of sodium salts, baking powder, and beverages, as a laboratory reagent, as a fire extinguisher, and in medicine as an antacid.
- sodium thiocyanate — a white powder or colorless, deliquescent crystals, NaSCN, used chiefly in organic synthesis and in medicine in the treatment of hypertension.
- solid-fuel heating — heating that uses solid fuel, such as coal or coke
- solitary sandpiper — a North American sandpiper, Tringa solitaria, of inland wetlands, having a brownish-gray, white-spotted back and whitish underparts.
- southampton island — an island in N Canada, in the Northwest Territories at the entrance to Hudson Bay. 19,100 sq. mi. (49,470 sq. km).
- southern rhodesian — a former name (until 1964) of Zimbabwe (def 1).
- stand at attention — military: stand straight
- standard deviation — a measure of dispersion in a frequency distribution, equal to the square root of the mean of the squares of the deviations from the arithmetic mean of the distribution.
- standard of living — a grade or level of subsistence and comfort in everyday life enjoyed by a community, class, or individual: The well-educated generally have a high standard of living.
- standing committee — a permanent committee, as of a legislature, society, etc., intended to consider all matters pertaining to a designated subject.