18-letter words containing i, p, r
- sonic depth finder — a sonar instrument that uses echolocation to measure depths under water.
- special prosecutor — (formerly) an independent counsel.
- special relativity — the state or fact of being relative.
- specialist teacher — a teacher with expertise in working with children with special educational needs, such as dyslexia
- specimen signature — a signature to be compared to an original signature in order to verify someone's identity
- 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
- spectropolarimeter — an instrument for determining the extent to which plane-polarized light of various wavelengths is rotated by certain solutions, consisting of a combination of a spectroscope and a polarimeter.
- spectropolariscope — an instrument combining the functions of a spectroscope with those of a polariscope.
- speech recognition — Computers. the computerized analysis of spoken words in order to identify the speaker, as in security systems, or to respond to voiced commands: the analysis is performed by finding patterns in the spectrum of the incoming sound and comparing them with stored patterns of elements of sound, as phones, or of complete words.
- speech synthesizer — device that imitates human voice
- sperry corporation — (company) The company which merged with the Burroughs Corporation to form Unisys Corporation. Divisions included Sperry Univac, Sperry Flight Systems, and others. Some of these were sold off after the merger.
- spherical geometry — the branch of geometry that deals with figures on spherical surfaces.
- spherical triangle — a triangle formed by arcs of great circles of a sphere.
- spike-tooth harrow — a harrow equipped with straight teeth on horizontal bars, usually employed to smooth and level plowed soil or seedbeds for planting or sowing.
- spirits of ammonia — a 10% solution of ammonia in alcohol
- split-level cooker — a cooker that is designed with a separate oven and hob so that they can be fitted wherever is most convenient in the kitchen
- spread one's wings — to make full use of one's abilities
- statutory sick pay — the pay an employee is legally entitled to when sick
- stratigraphic trap — A stratigraphic trap is a rock formation that contains hydrocarbons and is sealed by other rock formations.
- subatomic particle — physics:
- 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.
- super giant slalom — a slalom race in which the course is longer and has more widely spaced gates than in a giant slalom.
- super middleweight — a boxer weighing up to 168 pounds (75.6 kg), between middleweight and light heavyweight.
- superciliary ridge — browridge.
- superior vena cava — See under vena cava.
- superstring theory — any supersymmetric string theory in which each type of elementary particle is treated as a vibration of a single fundamental string (superstring) at a particular frequency.
- supporting actress — an actress playing a supporting role
- supportive therapy — any treatment, such as the intravenous administration of certain fluids, designed to reinforce or sustain the physiological well-being of a patient
- supraorbital ridge — browridge.
- surgical appliance — a specialized device used by somebody to relieve a particular medical condition
- surprise, surprise — You can say 'surprise, surprise' if you disapprove of something because it is not surprising or original, or could easily have been predicted.
- sustaining program — a radio or television program without a commercial sponsor.
- sweptwing aircraft — an aircraft which has wings that are swept (usually) backwards
- sympathetic strike — sympathy strike.
- sympathetic string — a thin wire string, as in various obsolete musical instruments, designed to vibrate sympathetically with the bowed or plucked strings to reinforce the sound.
- system-programming — a program, as an operating system, compiler, or utility program, that controls some aspect of the operation of a computer (opposed to application program).
- telephone receiver — a device, as in a telephone, that converts changes in an electric current into sound.
- temporal summation — the act or process of summing.
- terrestrial planet — inner planet.
- territory of papua — a former territory of Australia, consisting of SE New Guinea and adjacent islands: now part of Papua New Guinea
- the baptist church — any of various Protestant churches that believe in the baptism of believers
- the general public — the people in a society; people in general
- the operative word — If you describe a word as the operative word, you want to draw attention to it because you think it is important or exactly true in a particular situation.
- the practicalities — the real facts or details of a situation, as opposed to its theoretical aspects
- the-cocktail-party — a play in verse (1950) by T. S. Eliot.
- thiosulphuric acid — an unstable acid known only in solutions and in the form of its salts. Formula: H2S2O3
- thiruvananthapuram — a state in SW India: formerly the regions of Travancore and Cochin. 15,005 sq. mi. (38,836 sq. km). Capital: Thiruvananthapuram.