18-letter words containing d, o, a, n, i
- pseudointellectual — a person exhibiting intellectual pretensions that have no basis in sound scholarship.
- pull one's head in — the upper part of the body in humans, joined to the trunk by the neck, containing the brain, eyes, ears, nose, and mouth.
- qattara depression — a desert basin in the Libyan Desert, in NW Egypt: lowest point is 435 feet (133 meters) below sea level. 6950 sq. mi. (18,000 sq. km).
- quadratic equation — an equation containing a single variable of degree 2. Its general form is ax 2 + bx + c = 0, where x is the variable and a, b, and c are constants (a ≠ 0).
- quartz-iodine lamp — a type of tungsten-halogen lamp containing small amounts of iodine and having a quartz envelope, operating at high temperature and producing an intense light for use in car headlamps, etc
- radiation exposure — exposure to radiant energy or to the particles emitted in the transfer of radiant energy, esp the particles and gamma rays emitted in nuclear decay; exposure to radioactive substances
- radiation pressure — the pressure exerted on a surface by electromagnetic radiation or by sound waves.
- 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.
- radical expression — an expression in which radical signs appear.
- radio range beacon — a radio transmitter that utilizes two or more directional antennas and transmits signals differing with direction, permitting a flier receiving a signal to determine his or her approximate bearing from the transmitter without a radio compass.
- 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
- seafloor spreading — a process in which new ocean floor is created as molten material from the earth's mantle rises in margins between plates or ridges and spreads out.
- second triumvirate — the coalition and joint rule of the Roman Empire by Antony, Lepidus, and Octavian, begun in 43 bc
- secondary deviance — deviant behavior that results from being publicly labeled as deviant and treated as an outsider.
- secondary diagonal — a diagonal line or plane.
- secondary emission — the emission of electrons (secondary electrons) from a material that is bombarded with electrons or ions.
- secondary industry — manufacturing, services, etc.
- secondary offering — the sale of a large block of outstanding stock off the floor of an exchange, usually by a major stockholder.
- secondary syphilis — the second stage of syphilis, characterized by eruptions of the skin and mucous membrane.
- 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