21-letter words containing a, s, o
- rattle someone's cage — to upset or anger someone
- rayleigh distribution — (mathematics) A curve that yields a good approximation to the actual labour curves on software projects.
- reading comprehension — a text that students use to help them improve their reading skills, by reading it and answering questions relating to the text. Sometimes used as a test or examination of reading skills. A reading comprehension can be in the student's own or another language
- real operating system — (operating system, abuse) The sort the speaker is used to. People from the BSDophilic academic community are likely to issue comments like "System V? Why don't you use a *real* operating system?", people from the commercial/industrial Unix sector are known to complain "BSD? Why don't you use a *real* operating system?", and people from IBM object "Unix? Why don't you use a *real* operating system?" See holy wars, religious issues, proprietary, Get a real computer!.
- real-estate developer — a person who buys and develops houses, buildings, and land in order to sell them and make a profit from them
- recompression chamber — hyperbaric chamber.
- reconnaissance flight — a flight made by an aircraft in order to obtain military information about a particular place
- reconnaissance patrol — a patrol made by soldiers in order to obtain military information about a particular place
- redlegged grasshopper — a migratory grasshopper, Melanoplus femur-rubrum, of the southwestern and midwestern U.S., having reddish skin on the underside of the hind legs: an agricultural pest.
- registration document — a document giving identification details of a motor vehicle, including its manufacturer, date of registration, engine and chassis numbers, and owner's name
- relaxation oscillator — a nonsinusoidal oscillator, the timing of which is controlled by the charge and discharge time constants of resistance and capacitance components
- repatriation expenses — Repatriation expenses are the costs involved in transporting a claimant or their body back to their own country after they have been injured or killed in a foreign country.
- residual unemployment — the unemployment that remains in periods of full employment, as a result of those mentally, physically, or emotionally unfit to work
- rest on one's laurels — Also called bay, sweet bay. a small European evergreen tree, Laurus nobilis, of the laurel family, having dark, glossy green leaves. Compare laurel family.
- reverse polish syntax — postfix notation
- revillagigedo islands — an uninhabited island group belonging to Mexico, in the Pacific Ocean, SSW of the Baja California peninsula: Socorro is the largest island. 320 sq. mi. (830 sq. km).
- ring-around-the-rosey — a children's game in which the players sing while going around in a circle and squat when the lyrics “all fall down” are sung.
- rocky mountain locust — a migratory locust, Melanoplus spretus, that occurs in North America, especially the Great Plains, where swarms cause great damage to crops and other vegetation.
- rocky mountain oyster — mountain oyster.
- rolling in the aisles — (of an audience) overcome with laughter
- roodepoort-maraisburg — a city in S Transvaal, in the NE Republic of South Africa.
- rutherford scattering — the scattering of an alpha particle through a large angle with respect to the original direction of motion of the particle, caused by an atom (Rutherford atom) with most of the mass and all of the positive electric charge concentrated at a center or nucleus.
- s-k reduction machine — An abstract machine defined by Professor David Turner to evaluate combinator expressions represented as binary graphs. Named after the two basic combinators, S and K.
- safe in the knowledge — If you do something safe in the knowledge that something else is the case, you do the first thing confidently because you are sure of the second thing.
- saint anthony's cross — tau cross.
- saint elias mountains — a mountain range between SE Alaska and the SW Yukon, Canada. Highest peak: Mount Logan, 5959 m (19 550 ft)
- saint-maur-des-fosses — a town in N central France, near Paris, on the Marne River.
- salam-weinberg theory — the electroweak theory.
- sales finance company — a finance company that purchases, at a discount, installment contracts from dealers or that finances retail sales.
- sampling distribution — the distribution of a statistic based on all possible random samples that can be drawn from a given population.
- san gabriel mountains — a mountain range in S California, N of Los Angeles. Highest peak, San Antonio Peak, 10,080 feet (3072 meters).
- san gorgonio mountain — a mountain in S California: highest peak in the San Bernardino Mountains. 11,502 feet (3506 meters).
- sanitation department — the department of local government responsible for collecting and disposing of refuse
- santo tome de guayana — a city in NE Venezuela, on the Orinoco River.
- sao bernardo do campo — a city in SE Brazil, SE of São Paulo.
- sao jose do rio preto — a city in SE Brazil, NW of São Paulo.
- sao tome and principe — Democratic Republic of, a republic in W Africa, comprising the islands of São Tomé and Príncipe, in the Gulf of Guinea, N of the equator: a former overseas province of Portugal; gained independence in 1975. 372 sq. mi. (964 sq. km). Capital: São Tomé.
- saponification number — the number of milligrams of potassium hydroxide required to saponify one gram of a given ester, especially a glyceride.
- satisficing behaviour — the form of behaviour demonstrated by firms who seek satisfactory profits and satisfactory growth rather than maximum profits
- saving your reverence — a form of apology for using an obscene or taboo expression
- scalar multiplication — an operation used in the definition of a vector space in which the product of a scalar and a vector is a vector, the operation is distributive over the addition of both scalars and vectors, and is associative with multiplication of scalars
- scalar triple product — the volume of the parallelepiped defined by three given vectors, u, v, and w, usually represented as u·v 1 (v×w), [ uvw ], or (uvw), where × denotes a cross product and · denotes an inner product.
- scarlet monkey flower — any of various plants belonging to the genus Mimulus, of the figwort family, as M. cardinalis (scarlet monkey flower) having spotted flowers that resemble a face.
- schema definition set — (SDS) Something in Portable Common Tool Environment.
- schlieren photography — a type of photography which records schlieren
- scholastic philosophy — the system of philosophy, theology, and teaching that dominated medieval western Europe and was based on the writings of the Church Fathers and (from the 12th century) Aristotle, the Greek philosopher (384–322 bc)
- school of hard knocks — the experience gained from living, especially from disappointment and hard work, regarded as a means of education: The only school he ever attended was the school of hard knocks.
- scintillation counter — a device for detecting and measuring radioactivity, having a crystal scintillator, a photoelectric cell sensitive to the light from scintillations, and an amplifier.
- scorched earth policy — a military practice of devastating the property and agriculture of an area before abandoning it to an advancing enemy.
- scorched-earth policy — a military practice of devastating the property and agriculture of an area before abandoning it to an advancing enemy.