18-letter words containing p, r, o, d, u
- pitch-and-run shot — chip shot.
- 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.
- 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.
- pour cold water on — If someone pours cold water on a plan or idea, they criticize it so much that people lose their enthusiasm for it.
- predation pressure — the effect of predation upon a population, resulting in the decrease in size of that population.
- prefect of studies — a senior master in a Jesuit school or college
- prepare the ground — make conditions ready
- process scheduling — multitasking
- product acceptance — the verification or acceptance that a manufactured item meets required specifications or standards and is usable for its purpose
- product life cycle — the four stages (introduction, growth, maturity, and decline) into one of which the sales of a product fall during its market life
- production company — an organization which produces, films, plays, television or radio programmes
- production control — the planning and supervision of manufacturing activities to ensure that goods will be produced on time at the lowest possible cost.
- production manager — a supervisor of the budget, crew and other details in the production of a film or play
- productivity bonus — an extra payment made to workers for being more productive or yielding more favourable results than normal
- programme of study — the prescribed syllabus that pupils must be taught at each key stage in the National Curriculum
- prometheus unbound — a drama in verse (1820) by Shelley.
- protective custody — detention of a person by the police solely as protection against a possible attack or reprisal by someone.
- 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.
- pseudotuberculosis — an acute, sometimes fatal disease of rodents, birds, and other animals, including humans, caused by the bacterium Yersinia (Pasteurella) pseudotuberculosis, and characterized by the formation of nodules resembling those that result from tuberculosis.
- 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.
- put your foot down — If someone puts their foot down, they use their authority in order to stop something happening.
- pyromucic aldehyde — furfural.
- pyrosulphuric acid — a fuming liquid acid made by adding sulphur trioxide to concentrated sulphuric acid. Formula: H2S2O7
- 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.
- red-spotted purple — any color having components of both red and blue, such as lavender, especially one deep in tone.
- reproduction proof — repro proof.
- shop till you drop — If you shop till you drop, you do a large amount of shopping.
- sodium-vapour lamp — a type of electric lamp consisting of a glass tube containing neon and sodium vapour at low pressure through which an electric current is passed to give an orange light. They are used in street lighting
- solubility product — the maximum number of undissociated ions, of an electrolyte in a saturated solution, capable at a given temperature of remaining in equilibrium with the undissolved phase of the solution.
- sound spectrograph — an electronic device for recording a sound spectogram.
- subsidiary company — a company whose controlling interest is owned by another company.
- summary proceeding — a mode of trial authorized by statute to be held before a judge without the usual full hearing.
- supraorbital ridge — browridge.
- thiosulphuric acid — an unstable acid known only in solutions and in the form of its salts. Formula: H2S2O3
- to hold your peace — If you hold or keep your peace, you do not speak, even though there is something you want or ought to say.
- to speak your mind — If you speak your mind, you say firmly and honestly what you think about a situation, even if this may offend or upset people.
- under-compensation — to compensate or pay less than is fair, customary, or expected.
- under-depreciation — decrease in value due to wear and tear, decay, decline in price, etc.
- work-study program — a program enabling high-school or college students to combine academic work with actual job experience.