18-letter words containing p, r, e, t, l
- quarter-wave plate — a crystal thin enough to cause a phase difference of 90° between the ordinary and extraordinary rays of polarized light, thereby converting circularly polarized light into plane polarized light.
- quartz-iodine lamp — a type of tungsten-halogen lamp containing small amounts of iodine and having a quartz envelope, operating at high temperature and producing an intense light for use in car headlamps, etc
- rational operation — any of the mathematical operations of addition, subtraction, multiplication, and division.
- real-time computer — a computer that can process data or information almost immediately
- red cluster pepper — a tropical, woody plant, Capsicum annuum fasciculatum, having erect, very pungent, red fruit in small clusters.
- red-spotted purple — any color having components of both red and blue, such as lavender, especially one deep in tone.
- redevelopment area — an urban area in which all or most of the buildings are demolished and rebuilt
- reentering polygon — a polygon having one or more reentering angles.
- registration plate — a plate mounted on the front and back of a motor vehicle bearing the registration number
- reinforced plastic — plastic with fibrous matter, such as carbon fibre, embedded in it to confer additional strength
- repayment schedule — a document detailing the specific terms of a borrower's loan, such as monthly payment, interest rate, due dates etc
- replacement engine — an engine used to replace or substitute an older or broken engine (in a vehicle, etc)
- reporters' gallery — an area in parliament reserved for journalists and reporters
- reprocessing plant — a plant where materials are treated in order to make them reusable
- resistance plasmid — any of a group of bacterial plasmids carrying genetic information that provide resistance to antibiotic drugs: some resistance plasmids are able to transfer themselves, and hence resistance, during conjugation
- resurrection plant — a desert plant, Selaginella lepidophylla, occurring from Texas to South America, having stems that curl inward when dry.
- retail price index — The retail price index is a list of the prices of typical goods which shows how much the cost of living changes from one month to the next.
- ribbon development — housing or commercial buildings built along a stretch of road.
- root canal therapy — endodontics.
- scripting language — a language that is used to write scripts, or executable sections of code that automate tasks.
- 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.
- self-deprecatingly — in a self-deprecating manner
- self-disparagement — the act of disparaging.
- self-preoccupation — the state of being preoccupied.
- self-tapping screw — a screw designed to tap its corresponding female thread as it is driven.
- separate but equal — pertaining to a racial policy, formerly practiced in some parts of the United States, by which black people could be segregated if granted equal opportunities and facilities, as for education, transportation, or jobs.
- september holidays — a period of time in September when people do not have to go to school, college or work
- 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.
- shatterproof glass — glass designed to resist shattering
- sheltered workshop — a place of employment for persons with disabilities where their rights are protected and their needs are met.
- shepherd satellite — a small moon orbiting near a planetary ring, whose gravitational pull helps confine the ring and the ring's extent.
- 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.
- sling psychrometer — a psychrometer so designed that the wet-bulb thermometer can be ventilated, to expedite evaporation, by whirling in the air.
- 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
- small pastern bone — the part of the foot of a horse, cow, etc., between the fetlock and the hoof.
- software backplane — (programming, tool) A CASE framework from Atherton.
- solitary sandpiper — a North American sandpiper, Tringa solitaria, of inland wetlands, having a brownish-gray, white-spotted back and whitish underparts.
- 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
- 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.
- spectrofluorometer — 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.
- 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.
- 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