18-letter words containing p, s, i, o
- 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.
- resurrection plant — a desert plant, Selaginella lepidophylla, occurring from Texas to South America, having stems that curl inward when dry.
- retirement pension — income: no longer at work
- rhodes scholarship — one of a number of scholarships at Oxford University, established by the will of Cecil Rhodes, for selected students (Rhodes scholars) from the British Commonwealth and the United States.
- safety-deposit box — a lockable metal box or drawer, especially in a bank vault, used for safely storing valuable papers, jewelry, etc.
- scholarship holder — a person who, because of academic merit, receives financial aid for their studies
- scissors-and-paste — designating or of a piece of writing that has been assembled from a variety of sources rather than by original research, often in a hasty or uninspired way
- seafloor spreading — a process in which new ocean floor is created as molten material from the earth's mantle rises in margins between plates or ridges and spreads out.
- seasonal promotion — Seasonal promotions are items marketed to customers at the appropriate time of year, such as coats in the winter and bathing suits in the summer.
- secondary syphilis — the second stage of syphilis, characterized by eruptions of the skin and mucous membrane.
- self-comprehending — to understand the nature or meaning of; grasp with the mind; perceive: He did not comprehend the significance of the ambassador's remark.
- self-contemplation — the act or process of thinking about oneself or one's values, beliefs, behavior, etc.
- self-preoccupation — the state of being preoccupied.
- semiprecious stone — See at semiprecious.
- 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
- septic sore throat — an acute, toxic, streptococcus infection of the throat producing fever, tonsillitis, and other serious effects.
- set priority level — (SPL) The way traditional Unix kernels implement mutual exclusion by running code at high interrupt priority levels and thus blocking lower level interrupts.
- shape-note singing — a traditional style of a capella singing using shape-note notation.
- shipping container — a large, strong container, usually of metal, used to store goods in during shipment
- shipping documents — documents relating to the sending of a shipment of goods, for example containing details of contents, weight, value etc.
- shoot from the hip — the act of shooting with a bow, firearm, etc.
- shop till you drop — If you shop till you drop, you do a large amount of shopping.
- shotgun microphone — a directional microphone with a narrow-angle range of sensitivity.
- shunting operation — an operation in which rail coaches are manoeuvred
- silvery spleenwort — a fern, Diplazium pycnocarpon, of eastern North America, having fronds from 20 to 30 inches (50.8 to 76.2 cm) long on yellowish-green stalks.
- simple enumeration — a procedure for arriving at empirical generalizations by haphazard accumulation of positive instances.
- sleeping policeman — a bump built across roads, esp in housing estates, to deter motorists from speeding
- sling psychrometer — a psychrometer so designed that the wet-bulb thermometer can be ventilated, to expedite evaporation, by whirling in the air.
- slip of the tongue — If you describe something you said as a slip of the tongue, you mean that you said it by mistake.
- 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
- sociopsychological — of, relating to, or characterized by interrelated social and psychological factors.
- soda-lime feldspar — plagioclase.
- sodium hyposulfite — sodium thiosulfate.
- sodium polysulfide — a yellow-brown, water-soluble, granular powder, Na 2 S n , used chiefly in the manufacture of sulfur dyes, insecticides, and synthetic rubber.
- 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
- solitary sandpiper — a North American sandpiper, Tringa solitaria, of inland wetlands, having a brownish-gray, white-spotted back and whitish underparts.
- 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.
- something to spare — a surplus of something
- sonic depth finder — a sonar instrument that uses echolocation to measure depths under water.
- southampton island — an island in N Canada, in the Northwest Territories at the entrance to Hudson Bay. 19,100 sq. mi. (49,470 sq. km).
- spackling compound — spackle
- spaghetti junction — an interchange, usually between motorways, in which there are a large number of underpasses and overpasses and intersecting roads used by a large volume of high-speed traffic
- spanish succession — War of thea war (1701-14) between European powers disputing the succession to the Spanish throne
- special collection — a collection of materials segregated from a general library collection according to form, subject, age, condition, rarity, source, or value.
- special prosecutor — (formerly) an independent counsel.
- specific viscosity — a measure of the resistance to flow of a fluid, expressed as the ratio of the absolute viscosity of the fluid to that of a reference fluid (usually water in the case of liquids)
- spectrocolorimetry — the quantitative measure of colors by spectrophotometry.
- spectrofluorimeter — an instrument in which the spectrum of secondarily emitted fluorescent light is used to identify chemical compounds.
- 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