21-letter words containing r, e, t, i, l
- nonrestrictive clause — a relative clause that describes or supplements but is not essential in establishing the identity of the antecedent and is usually set off by commas in English. In This year, which has been dry, is bad for crops the clause which has been dry is a nonrestrictive clause.
- nonviolent resistance — passive resistance, peaceful protest
- north atlantic treaty — the treaty (1949) signed by 12 countries, providing for the establishment of NATO.
- northumberland strait — the part of the Gulf of St. Lawrence that separates Prince Edward Island from New Brunswick and Nova Scotia, in SE Canada. About 200 miles (320 km) long; 9–30 miles (15–48 km) wide.
- nuclear cross section — cross section (def 7).
- nuclear power station — a station or plant where nuclear energy is converted into heat, electricity, etc
- objective correlative — a completely depicted situation or chain of events that objectifies a particular emotion in such a way as to produce or evoke that emotion in the reader.
- observation satellite — an unmanned satellite that observes the earth and gathers data
- oil-in-water emulsion — An oil-in-water emulsion is a mixture in which an oily medicine is dispersed in water or other liquid.
- old spanish practices — irregular practices among a group of workers to gain increased financial allowances, reduced working hours, etc
- open trading protocol — Internet Open Trading Protocol
- operational amplifier — a high-gain, high-input impedance amplifier, usually an integrated circuit, that can perform mathematical operations when suitably wired.
- operational semantics — (theory) A set of rules specifying how the state of an actual or hypothetical computer changes while executing a program. The overall state is typically divided into a number of components, e.g. stack, heap, registers etc. Each rule specifies certain preconditions on the contents of some components and their new contents after the application of the rule. It is similar in spirit to the notion of a Turing machine, in which actions are precisely described in a mathematical way. Compuare axiomatic semantics, denotational semantics.
- ophthalmia neonatorum — inflammation of the eyes of a newborn child due to an infectious disease, as gonorrhea, contracted during birth from the infected mother.
- optical double (star) — double star (sense 2)
- ortho-dichlorobenzene — a colorless liquid with a pleasant odor, C 6 H 4 Cl 2 , used as a solvent for a wide range of organic materials.
- orthogonal projection — a two-dimensional graphic representation of an object in which the projecting lines are at right angles to the plane of the projection. Also called orthogonal projection. Compare isometric (def 5).
- paradoxical intention — (in psychotherapy) the deliberate practice of a neurotic habit or thought, undertaken in order to remove it
- parliamentary inquiry — a question asked of the presiding officer of a parliament in relation to parliamentary law
- partial reinforcement — the process of randomly rewarding an organism for making a response on only some of the occasions it makes it
- partially ordered set — a set in which a relation as “less than or equal to” holds for some pairs of elements of the set, but not for all.
- pellitory-of-the-wall — an urticaceous plant, P. diffusa, of the S and W European genus Parietaria, which grows in crevices and has long narrow leaves and small pink flowers
- personality inventory — a questionnaire designed to measure personality types or characteristics.
- photoelectric current — photocurrent.
- picture quality scale — (graphics) (PQS) A system for rating image quality based upon features of images that affect their perception by the human eye, rather than the traditional signal-to-noise ratio which examines differences for every single pixel.
- piezoelectric ceramic — any ceramic that exhibits piezoelectric properties.
- piezoelectric crystal — a crystal, such as quartz, that produces a potential difference across its opposite faces when under mechanical stress
- pipelined burst cache — Pipeline Burst Cache
- place of articulation — the location at which two speech organs approach or come together in producing a speech sound, as in the contact of the tongue and the teeth to form a dental sound. Also called point of articulation. Compare articulator (def 2).
- plate glass insurance — Plate glass insurance is insurance coverage against damage to or breakage of large panes of glass such as shop windows.
- play russian roulette — take a foolish risk
- political correctness — Political correctness is the attitude or policy of being extremely careful not to offend or upset any group of people in society who have a disadvantage, or who have been treated differently because of their sex, race, or disability.
- politically incorrect — not politically correct; potentially offensive to a particular group of people: politically incorrect jokes.
- polygenic inheritance — the heredity of complex characters that are determined by a large number of genes, each one usually having a relatively small effect.
- populist shop steward — a shop steward who operates in a delegate role, putting the immediate interests of his members before union principles and policies
- posterior probability — the probability assigned to some parameter or to an event on the basis of its observed frequency in a sample, and calculated from a prior probability by Bayes' theorem
- prefect of discipline — a senior master in a Jesuit school or college
- premature ejaculation — a male psychosexual disorder in which ejaculation occurs soon after the commencement of sexual intercourse.
- primitive dicotyledon — any living relative of early angiosperms that branched off before the evolution of monocotyledons and eudicotyledons. The group comprises about 5 per cent of the world's plants
- prince rupert's metal — a brass composed of from about 60 to 85 percent copper and about 15 to 40 percent zinc, used to imitate gold.
- private member's bill — In Britain, a Private Member's Bill is a law that is proposed by a Member of Parliament acting as an individual rather than as a member of his or her political party.
- processor direct slot — (hardware) (PDS) Apple Computer's name for a local bus connection. Most Macintoshes have only one PDS connector. Different Apple computers have different PDS specifications.
- projection television — a television picture display system consisting of a special receiver and an optical system that projects an enlarged picture on a screen.
- propantheline bromide — a substance, C 2 3 H 3 0 BrNO 3 , used in the treatment of peptic ulcers.
- protective coloration — coloration or anything likened to it that eliminates or reduces visibility or conspicuousness.
- public address system — loudspeaker
- public health service — the agency that is responsible for the health of the general public
- public-address system — a combination of electronic devices that makes sound audible via loudspeakers to many people, as in an auditorium or out of doors.
- public-key encryption — (cryptography) (PKE, Or "public-key cryptography") An encryption scheme, introduced by Diffie and Hellman in 1976, where each person gets a pair of keys, called the public key and the private key. Each person's public key is published while the private key is kept secret. Messages are encrypted using the intended recipient's public key and can only be decrypted using his private key. This is often used in conjunction with a digital signature. The need for sender and receiver to share secret information (keys) via some secure channel is eliminated: all communications involve only public keys, and no private key is ever transmitted or shared. Public-key encryption can be used for authentication, confidentiality, integrity and non-repudiation. See also knapsack problem.
- pulse height analyser — a multichannel analyser that sorts pulses into selected amplitude ranges