19-letter words containing s, u, d, o, r
- noughts-and-crosses — tick-tack-toe (def 1).
- old church slavonic — the oldest attested Slavic language, an ecclesiastical language written first by Cyril and Methodius in a Bible translation of the 9th century and continued in use for about two centuries. It represents the South Slavic, Bulgarian dialect of 9th-century Salonika with considerable addition of other South and West Slavic elements. Abbreviation: OCS.
- olive-backed thrush — Swainson's thrush.
- on one's own ground — If you are on your own ground, you are in a place or situation in which you feel confident because you are very familiar with it.
- optical double star — two stars that appear as one if not viewed through a telescope with adequate magnification, such as two stars that are separated by a great distance but are nearly in line with each other and an observer (optical double star) or those that are relatively close together and comprise a single physical system (physical double star)
- ordnance survey map — An Ordnance Survey map is a detailed map produced by the British or Irish government map-making organization.
- orthopaedic surgeon — a surgeon specializing in the branch of surgery concerned with disorders of the spine and joints and the repair of deformities of these parts
- orthopaedic surgery — surgery concerned with disorders of the spine and joints and the repair of deformities of these parts
- percussion drilling — Percussion drilling is a drilling method which involves lifting and dropping heavy tools to break rock, and uses steel casing tubes to stop the borehole from collapsing.
- peroxysulfuric acid — persulfuric acid (def 1).
- police headquarters — building where police are stationed
- potassium hydroxide — a white, deliquescent, water-soluble solid, KOH, usually in the form of lumps, sticks, or pellets, that upon solution in water generates heat: used chiefly in the manufacture of soap, as a laboratory reagent, and as a caustic.
- printing discussion — [XEROX PARC] A protracted, low-level, time-consuming, generally pointless discussion of something only peripherally interesting to all.
- priority scheduling — (operating system) Processes scheduling in which the scheduler selects tasks to run based on their priority as opposed to, say, a simple round-robin. Priorities may be static or dynamic. Static priorities are assigned at the time of creation, while dynamic priorities are based on the processes' behaviour while in the system. For example, the scheduler may favour I/O-intensive tasks so that expensive requests can be issued as early as possible. A danger of priority scheduling is starvation, in which processes with lower priorities are not given the opportunity to run. In order to avoid starvation, in preemptive scheduling, the priority of a process is gradually reduced while it is running. Eventually, the priority of the running process will no longer be the highest, and the next process will start running. This method is called aging.
- profitability study — a study of how much profit a company, organization, etc, makes or how profitable it is
- progressive judaism — Reform Judaism.
- pseudo-aristocratic — of or relating to government by an aristocracy.
- pseudo-biographical — of or relating to a person's life: He's gathering biographical data for his book on Milton.
- pseudo-conservative — disposed to preserve existing conditions, institutions, etc., or to restore traditional ones, and to limit change.
- pseudo-experimental — pertaining to, derived from, or founded on experiment: an experimental science.
- pseudo-hieroglyphic — noting or pertaining to a script dating from the second millennium b.c. that appears to be syllabic and to represent the Phoenician language and that is inscribed on objects found at Byblos.
- pseudo-intransitive — denoting an occurrence of a normally transitive verb in which a direct object is not explicitly stated or forms the subject of the sentence, as in Margaret is cooking or these apples cook well
- pseudo-professional — following an occupation as a means of livelihood or for gain: a professional builder.
- pseudohermaphrodite — an individual having internal reproductive organs of one sex and external sexual characteristics resembling those of the other sex or being ambiguous in nature. Compare hermaphrodite (def 1).
- pseudorandom number — (programming) One of a sequence of numbers generated by some algorithm so as to have an even distribution over some range of values and minimal correlation between successive values. Pseudorandom numbers are used in simulation and encryption. They are pseudorandom not random because the sequence eventually repeats exactly and is entirely determined by the initial conditions. One of the simplest algorithms is x[i+1] = (a * x[i] + c) mod m but this repeats after at most m numbers and successive numbers are closely related. Better algorithms generally use more previous numbers to calculate the next number.
- radius of curvature — the absolute value of the reciprocal of the curvature at a point on a curve.
- red-shouldered hawk — a North American hawk, Buteo lineatus, having rufous shoulders.
- regular icosahedron — an icosahedron in which each of the faces is an equilateral triangle
- reindustrialization — the revitalization of an industry or industrial society through government aid and tax incentives, modernization of factories and machinery, etc.
- religious education — religion as school subject
- reserved occupation — in time of war, an occupation from which one will not be called up for military service
- ride roughshod over — shod with horseshoes having projecting nails or points.
- scale down (or up) — to reduce (or increase), often according to a fixed ratio or proportion
- screen actors guild — a labor union for motion-picture performers, founded in 1933. Abbreviation: SAG.
- secondary education — education at high-school level
- secondary qualities — one of the qualities attributed by the mind to an object perceived, such as color, temperature, or taste.
- secondary structure — the arrangement of a polypeptide into a regular alpha helix, beta structure, or random coil configuration by the formation of intramolecular hydrogen bonds along the length of the chain.
- semiconductor laser — a laser in which a semiconductor is the light-emitting source, used in many medical procedures.
- sexual reproduction — reproduction involving the union of gametes.
- sharp-tailed grouse — a grouse, Pedioecetes phasianellus, of prairies and open forests of western North America, similar in size to the prairie chicken but with a more pointed tail.
- sidereal hour angle — the angle, measured westward through 360°, between the hour circle passing through the vernal equinox and the hour circle of a celestial body.
- simple closed curve — a curve that is closed and that has no loops or points missing; a curve for which there exists a homeomorphism mapping it to a circle.
- slate-colored junco — the eastern subspecies of the dark-eyed junco, Junco hyemalis, having grayer plumage than the several western subspecies.
- smokestack industry — A smokestack industry is a traditional industry such as heavy engineering or manufacturing, rather than a modern industry such as electronics.
- sodium hydrosulfite — a white, crystalline, water-soluble powder, Na 2 S 2 O 4 , used as a reducing agent, especially in dyeing, and as a bleach.
- sodium hypochlorite — a pale-green, crystalline compound, NaOCl, unstable in air, soluble in cold water, decomposes in hot water: used as a bleaching agent for paper and textiles, in water purification, in household use, and as a fungicide.
- soft-shelled turtle — any of numerous aquatic turtles of the family Trionychidae, inhabiting North America, Asia, and Africa, having the shell covered with flexible, leathery skin instead of horny plates.
- solid of revolution — a three-dimensional figure formed by revolving a plane area about a given axis.
- south african dutch — the Boers.
- staff-student ratio — the ratio of teachers to pupils or students in a school, college, or university