18-letter words containing a, d, r, s, t
- optical disc drive — optical disk drive
- optical disk drive — (hardware) (Or "optical disc drive", "optical storage") A generic term for any device that reads and/or writes optical media, i.e. compact discs, DVDs and/or Blu-ray discs or future media that uses light (from a small laser) to read data off a removable, rotating disk. At least one such drive is commonly installed in most personal computers to allow them to play and/or record audio and video media and load and store data such as program installers. The floppy disk has been replaced by optical media due to its vastly greater capacity, e.g. 50,000 megabytes for a dual-layer blu-ray disc compared with 1.5 megabytes for a floppy (over 30,000 times as much).
- optical soundtrack — the final soundtrack on a motion picture, which appears as a band of black and white serrations along a strip of film to the left of the composite print. Light is shined through the serrations and is converted to audible sound.
- order of australia — an order awarded to Australians for outstanding achievement or for service to Australia or to humanity at large; established in 1975
- organic solidarity — social cohesiveness that is based on division of labor and interdependence and is characteristic of complex, industrial societies.
- orthotungstic acid — an oxyacid acid of tungsten. Formula: H2WO4
- osteitis deformans — Paget's disease.
- osteoradionecrosis — bone tissue death induced by radiation.
- overdraft interest — interest charged on money withdrawn in excess of the credit balance of a bank or building society account
- paediatric nursing — the branch of nursing concerned with the care of children
- parathyroid glands — any of several small oval glands usually lying near or embedded in the thyroid gland.
- pass the hat round — to collect money, as for a cause
- 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
- per ardua ad astra — through difficulties to the stars: the motto of the RAF
- permanent hardness — hardness of water that cannot be removed by boiling as it results mainly from the presence of calcium and magnesium chlorides and sulphates
- permanent resident — an immigrant who has been given official residential status, often prior to being granted citizenship
- phosphatidylserine — any of a class of phospholipids occurring in biological membranes and fats
- pitch-and-run shot — chip shot.
- 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.
- 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.
- programme of study — the prescribed syllabus that pupils must be taught at each key stage in the National Curriculum
- pseudo-anarchistic — a person who advocates or believes in anarchy or anarchism.
- put heads together — the upper part of the body in humans, joined to the trunk by the neck, containing the brain, eyes, ears, nose, and mouth.
- 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).
- quinacrine mustard — a nitrogen mustard derived from mepacrine and used as a stain for chromosomes
- 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 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.
- 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.
- rail rapid transit — a system of rail transit within an urban area that has exclusive right of way either below, above, or on the ground and so is capable of relatively high operating speed. Abbreviation: RRT.
- 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).
- rear its ugly head — the upper part of the body in humans, joined to the trunk by the neck, containing the brain, eyes, ears, nose, and mouth.
- 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 charity — official aid organization
- 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
- repayment schedule — a document detailing the specific terms of a borrower's loan, such as monthly payment, interest rate, due dates etc