18-letter words containing a, r, o, y, s
- processionary moth — a moth of the family Thaumetopoeidae, esp the oak processionary moth (Thaumetopoea processionea), the larvae of which leave the communal shelter nightly for food in a V-shaped procession
- programme of study — the prescribed syllabus that pupils must be taught at each key stage in the National Curriculum
- property insurance — insurance coverage for land and housing
- proprietary rights — rights of ownership
- psychogalvanometer — a type of galvanometer for detecting and measuring psychogalvanic currents.
- psychopharmacology — the branch of pharmacology dealing with the psychological effects of drugs.
- psychotherapeutics — psychotherapy.
- pulmonary embolism — the blockage of a pulmonary artery, often by a blood clot, that stops the flow of blood to the lungs and which can result in death if untreated
- pyrosulphuric acid — a fuming liquid acid made by adding sulphur trioxide to concentrated sulphuric acid. Formula: H2S2O7
- quality of service — (communications, networking) (QoS) The performance properties of a network service, possibly including throughput, transit delay, priority. Some protocols allow packets or streams to include QoS requirements.
- 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.
- raman spectroscopy — a form of spectroscopy which uses the Raman effect for studying molecules
- range of stability — the angle to the perpendicular through which a vessel may be heeled without losing the ability to right itself.
- 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
- reporters' gallery — an area in parliament reserved for journalists and reporters
- respiratory arrest — cessation of breathing
- respiratory system — the system by which oxygen is taken into the body and an exchange of oxygen and carbon dioxide takes place; in mammals the system includes the nasal passages, pharynx, trachea, bronchi, and lungs.
- restoration comedy — English comedy of the period of the Restoration, stressing manners and social satire.
- reversionary bonus — a bonus added to the sum payable on death or at the maturity of a with-profits assurance policy
- revolutionary wars — American Revolution.
- rheims-douay bible — Douay Bible.
- ride a hobby horse — an activity or interest pursued for pleasure or relaxation and not as a main occupation: Her hobbies include stamp-collecting and woodcarving.
- rosebay willowherb — a perennial onagraceous plant, Chamerion (formerly Epilobium) angustifolium, that has spikes of deep pink flowers and is widespread in open places throughout N temperate regions
- rotary clothesline — an apparatus of radiating spokes that support lines on which clothes are hung to dry
- safety regulations — regulations or rules that are put in place to ensure a product, event, etc, is safe and not dangerous
- 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.
- 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.
- scottish secretary — the Secretary of State for Scotland, head of the Scotland Office, a UK government department with responsibility for some Scottish affairs
- search-and-destroy — designed to find and destroy by bombing etc
- secondary consumer — (in the food chain) a carnivore that feeds only upon herbivores.
- 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 recovery — extraction of oil or natural gas under artificially induced pressure after the natural flow has ceased.
- secondary syphilis — the second stage of syphilis, characterized by eruptions of the skin and mucous membrane.
- secretary of state — the head and chief administrator of the U.S. Department of State. Compare foreign minister.
- self-contradictory — an act or instance of contradicting oneself or itself.
- semi-microanalysis — any analytical method in which the weight of the sample is between 10 and 100 milligrams.
- separation anxiety — the normal fear and apprehension expressed by infants when removed from their mothers or approached by strangers.
- september holidays — a period of time in September when people do not have to go to school, college or work
- shaggy dog (story) — a long, rambling joke, typically involving ludicrously unreal or irrational behavior and usually having an irrelevant conclusion
- shugart technology — Seagate Technology
- slow-motion replay — a showing again in slow motion of a sequence of action, esp of part of a sporting contest immediately after it happens
- solitary sandpiper — a North American sandpiper, Tringa solitaria, of inland wetlands, having a brownish-gray, white-spotted back and whitish underparts.
- sound and the fury — a novel (1929) by William Faulkner.
- speak for yourself — If you say 'Speak for yourself' when someone has said something, you mean that what they have said is only their opinion or applies only to them.
- spectroheliography — the process of obtaining an image of the sun in light of a particular wavelength, such as calcium or hydrogen, showing the distribution of the element over the surface and in the solar atmosphere, using a spectroheliograph