18-letter words containing a, p, r, o, s, i
- regular expression — 1. (text, operating system) (regexp, RE) One of the wild card patterns used by Perl and other languages, following Unix utilities such as grep, sed, and awk and editors such as vi and Emacs. Regular expressions use conventions similar to but more elaborate than those described under glob. A regular expression is a sequence of characters with the following meanings (in Perl, other flavours vary): An ordinary character (not one of the special characters discussed below) matches that character. A backslash (\) followed by any special character matches the special character itself. The special characters are: "." matches any character except newline; "RE*" (where RE is any regular expression and the "*" is called the "Kleene star") matches zero or more occurrences of RE. If there is any choice, the longest leftmost matching string is chosen. "^" at the beginning of an RE matches the start of a line and "$" at the end of an RE matches the end of a line. (RE) matches whatever RE matches and \N, where N is a digit, matches whatever was matched by the RE between the Nth "(" and its corresponding ")" earlier in the same RE. Many flavours use \(RE\) instead of just (RE). The concatenation of REs is a RE that matches the concatenation of the strings matched by each RE. RE1 | RE2 matches whatever RE1 or RE2 matches. \< matches the beginning of a word and \> matches the end of a word. Many flavours use "\b" instead as the special character for "word boundary". RE{M} matches M occurences of RE. RE{M,} matches M or more occurences of RE. RE{M,N} matches between M and N occurences. Other flavours use RE\{M\} etc. Perl provides several "quote-like" operators for writing REs, including the common // form and less common ??. A comprehensive survey of regexp flavours is found in Friedl 1997 (see below). 2. Any description of a pattern composed from combinations of symbols and the three operators: Concatenation - pattern A concatenated with B matches a match for A followed by a match for B. Or - pattern A-or-B matches either a match for A or a match for B. Closure - zero or more matches for a pattern. The earliest form of regular expressions (and the term itself) were invented by mathematician Stephen Cole Kleene in the mid-1950s, as a notation to easily manipulate "regular sets", formal descriptions of the behaviour of finite state machines, in regular algebra.
- reinforced plastic — plastic with fibrous matter, such as carbon fibre, embedded in it to confer additional strength
- reprocessing plant — a plant where materials are treated in order to make them reusable
- respiratory arrest — cessation of breathing
- 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.
- 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.
- 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-preoccupation — the state of being preoccupied.
- 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.
- shipping container — a large, strong container, usually of metal, used to store goods in during shipment
- shunting operation — an operation in which rail coaches are manoeuvred
- simple enumeration — a procedure for arriving at empirical generalizations by haphazard accumulation of positive instances.
- 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
- soda-lime feldspar — plagioclase.
- 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.
- something to spare — a surplus of something
- special prosecutor — (formerly) an independent counsel.
- 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.
- 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.
- 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
- 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
- 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.
- superior vena cava — See under vena cava.
- 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.
- sustaining program — a radio or television program without a commercial sponsor.
- 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).
- temporal summation — the act or process of summing.
- thiosulphuric acid — an unstable acid known only in solutions and in the form of its salts. Formula: H2S2O3
- to cast aspersions — If you cast aspersions on someone or something, you suggest that they are not very good in some way.
- to play favourites — to display favouritism
- to scrape a living — If you say that someone scrapes a living or scratches a living, you mean that they manage to earn enough to live on, but it is very difficult. In American English, you say they scrape out a living or scratch out a living.
- to speak your mind — If you speak your mind, you say firmly and honestly what you think about a situation, even if this may offend or upset people.