18-letter words containing a, d, r, i, t
- partial derivative — the derivative of a function with respect to one of its variables with all other variables held constant.
- passing-out parade — a ceremonial parade of cadets who have completed their training
- pectoral sandpiper — an American sandpiper, Calidris melanotos, the male of which, when courting, inflates its chest conspicuously.
- pedal steel guitar — an oblong, floor-mounted electrified guitar, usually having ten strings, fretted with a steel bar and producing a wailing sound that is modulated by use of a foot pedal.
- pedestrian traffic — the people coming and going on foot in a street, town, etc
- permanent resident — an immigrant who has been given official residential status, often prior to being granted citizenship
- phantom withdrawal — the unauthorized removal of funds from a bank account using an automated teller machine
- phosphatidylserine — any of a class of phospholipids occurring in biological membranes and fats
- phthalic anhydride — a white, crystalline, slightly water-soluble solid, C 8 H 4 O 3 , used chiefly in the manufacture of dyes, alkyd resins, and plasticizers.
- pileolated warbler — either of two western subspecies of Wilson's warbler.
- pitch-and-run shot — chip shot.
- point d'angleterre — a bobbin lace in which the design is worked out with either a needle or bobbin.
- point of departure — Nautical. the precise location of a vessel, established in order to set a course, especially in beginning a voyage in open water.
- population pyramid — a graph showing the distribution of a population by sex, age, etc.
- portrait of a lady — a novel (1881) by Henry James.
- positively charged — having a positive charge
- postviral syndrome — debilitating condition occurring as a sequel to viral illness
- potassium chloride — a white or colorless, crystalline, water-soluble solid, KCl, used chiefly in the manufacture of fertilizers and mineral water, and as a source of other potassium compounds.
- potassium fluoride — a white, crystalline, hygroscopic, toxic powder, KF, used chiefly as an insecticide, a disinfectant, and in etching glass.
- potential gradient — the rate of change of potential with respect to distance in the direction of greatest change.
- predation pressure — the effect of predation upon a population, resulting in the decrease in size of that population.
- predicate calculus — predicate logic
- presenile dementia — a form of dementia, of unknown cause, starting before a person is old
- preservation order — In Britain, a preservation order is an official order that makes it illegal for anyone to alter or destroy something such as an old building or an area of countryside.
- presidential suite — a suite of rooms, as in a hotel, suitable for a president or other head of state.
- prestidigitization — /pres`t*-di"j*-ti:-zay"sh*n/ 1. A term coined by Daniel Klein <[email protected]> for the act of putting something into digital notation via sleight of hand. 2. Data entry through legerdemain.
- primate of england — a title of the archbishop of Canterbury.
- production company — an organization which produces, films, plays, television or radio programmes
- production manager — a supervisor of the budget, crew and other details in the production of a film or play
- protocol data unit — (PDU) A packet of data passed across a network. The term implies a specific layer of the OSI seven layer model and a specific protocol.
- provably difficult — The set or property of problems for which it can be proven that no polynomial-time algorithm exists, only exponential-time algorithms.
- pseudo-anarchistic — a person who advocates or believes in anarchy or anarchism.
- pyramus and thisbe — (in Greek legend) two lovers of Babylon: Pyramus, wrongly supposing Thisbe to be dead, killed himself and she, encountering him in his death throes, did the same
- 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).
- quarry-tiled floor — a floor covered with square or diamond-shaped unglazed floor tiles
- 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
- quinacrine mustard — a nitrogen mustard derived from mepacrine and used as a stain for chromosomes
- racially motivated — motivated by (the hate or prejudice of) someone's race
- radiant efficiency — the ratio of the power emitted by a source of radiation to the power consumed by it
- 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.
- 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.
- radioactive series — a succession of elements initiated in the radioactive decay of a parent, as thorium or uranium, each of which decays into the next until a stable element, usually lead, is produced.
- 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.