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17-letter words containing d, e, n, u, a

  • natural deduction — (logic)   A set of rules expressing how valid proofs may be constructed in predicate logic. In the traditional notation, a horizontal line separates premises (above) from conclusions (below). Vertical ellipsis (dots) stand for a series of applications of the rules. "T" is the constant "true" and "F" is the constant "false" (sometimes written with a LaTeX \perp). "^" is the AND (conjunction) operator, "v" is the inclusive OR (disjunction) operator and "/" is NOT (negation or complement, normally written with a LaTeX \neg). P, Q, P1, P2, etc. stand for propositions such as "Socrates was a man". P[x] is a proposition possibly containing instances of the variable x, e.g. "x can fly". A proof (a sequence of applications of the rules) may be enclosed in a box. A boxed proof produces conclusions that are only valid given the assumptions made inside the box, however, the proof demonstrates certain relationships which are valid outside the box. For example, the box below labelled "Implication introduction" starts by assuming P, which need not be a true proposition so long as it can be used to derive Q. Truth introduction: - T (Truth is free). Binary AND introduction: ----------- | . | . | | . | . | | Q1 | Q2 | ----------- Q1 ^ Q2 (If we can derive both Q1 and Q2 then Q1^Q2 is true). N-ary AND introduction: ---------------- | . | .. | . | | . | .. | . | | Q1 | .. | Qn | ---------------- Q1^..^Qi^..^Qn Other n-ary rules follow the binary versions similarly. Quantified AND introduction: --------- | x . | | . | | Q[x] | --------- For all x . Q[x] (If we can prove Q for arbitrary x then Q is true for all x). Falsity elimination: F - Q (Falsity opens the floodgates). OR elimination: P1 v P2 ----------- | P1 | P2 | | . | . | | . | . | | Q | Q | ----------- Q (Given P1 v P2, if Q follows from both then Q is true). Exists elimination: Exists x . P[x] ----------- | x P[x] | | . | | . | | Q | ----------- Q (If Q follows from P[x] for arbitrary x and such an x exists then Q is true). OR introduction 1: P1 ------- P1 v P2 (If P1 is true then P1 OR anything is true). OR introduction 2: P2 ------- P1 v P2 (If P2 is true then anything OR P2 is true). Similar symmetries apply to ^ rules. Exists introduction: P[a] ------------- Exists x.P[x] (If P is true for "a" then it is true for all x). AND elimination 1: P1 ^ P2 ------- P1 (If P1 and P2 are true then P1 is true). For all elimination: For all x . P[x] ---------------- P[a] (If P is true for all x then it is true for "a"). For all implication introduction: ----------- | x P[x] | | . | | . | | Q[x] | ----------- For all x . P[x] -> Q[x] (If Q follows from P for arbitrary x then Q follows from P for all x). Implication introduction: ----- | P | | . | | . | | Q | ----- P -> Q (If Q follows from P then P implies Q). NOT introduction: ----- | P | | . | | . | | F | ----- / P (If falsity follows from P then P is false). NOT-NOT: //P --- P (If it is not the case that P is not true then P is true). For all implies exists: P[a] For all x . P[x] -> Q[x] ------------------------------- Q[a] (If P is true for given "a" and P implies Q for all x then Q is true for a). Implication elimination, modus ponens: P P -> Q ---------- Q (If P and P implies Q then Q). NOT elimination, contradiction: P /P ------ F (If P is true and P is not true then false is true).
  • nervous breakdown — (not in technical use) any disabling mental disorder requiring treatment.
  • neurodegenerative — Resulting in or characterized by degeneration of the nervous system, especially the neurons in the brain.
  • new guinea pidgin — the variety of Neo-Melanesian spoken in Papua New Guinea and neighbouring islands
  • newfoundland time — a form of civil time observed on the island of Newfoundland, one and one-half hours later than Eastern time and a half hour later than Atlantic time.
  • nonunderstandable — Not understandable.
  • nuclear deterrent — a country's nuclear weapons viewed as a deterrent to other countries from attacking
  • nuclear radiation — Physics. radiation in the form of elementary particles emitted by an atomic nucleus, as alpha rays or gamma rays, produced by decay of radioactive substances or by nuclear fission.
  • nuclear threshold — the point in war at which a combatant brings nuclear weapons into use
  • nursery education — education provided at a school for young children, usually from three to five years old
  • odds-on favourite — a person, team, horse, etc that is regarded as the most likely to win a competition
  • on the foundation — an endowment or legacy for the perpetual support of an institution such as a school or hospital
  • out of one's head — the upper part of the body in humans, joined to the trunk by the neck, containing the brain, eyes, ears, nose, and mouth.
  • performance drugs — the drugs that are taken illegally by athletes to enhance their sporting performance
  • phumiphon aduldet — (Phumiphon Aduldet; Bhumibol Adulyadej) born 1927, king of Thailand since 1946.
  • physical pendulum — any apparatus consisting of a body of possibly irregular shape allowed to rotate freely about a horizontal axis on which it is pivoted (distinguished from simple pendulum).
  • plug and feathers — an apparatus for splitting stone, consisting of two tapered bars (feathers) inserted into a hole drilled into the stone, between which a narrow wedge (plug) is hammered to spread them.
  • postural drainage — a therapy for clearing congested lungs by placing the patient in a position for drainage by gravity, often accompanied by percussion with hollowed hands.
  • potassium cyanide — a white, granular, water-soluble, poisonous powder, KCN, having a faint almondlike odor, used chiefly in metallurgy and photography.
  • prelingually deaf — deaf from birth or having acquired deafness before learning to speak
  • premiere danseuse — the leading female dancer in a ballet company.
  • pressure drawdown — Pressure drawdown is the difference between the reservoir pressure and the flowing wellbore pressure, which drives fluids from the reservoir into the wellbore.
  • pressure gradient — the change of pressure per unit distance
  • pressurized cabin — the cabin of an aircraft in which the air has been pressurized
  • primary education — junior, elementary schooling
  • private education — education provided by a private individual or organization, rather than by the state or a public body
  • product placement — Product placement is a form of advertising in which a company has its product placed where it can be clearly seen during a film or television programme.
  • production values — the quality of a media production (such as a film) in regards to elements such as colours, quality, style, etc
  • prudence crandallPrudence, 1803–90, U.S. educator and civil-rights activist.
  • pseudo-humanistic — a person having a strong interest in or concern for human welfare, values, and dignity.
  • psychoeducational — designating or of psychological methods, as intelligence tests, used in evaluating learning ability
  • pull your head in — be quiet!
  • purely and simply — You use purely and simply to emphasize that the thing you are mentioning is the only thing involved.
  • purple granadilla — the edible fruit of any of several species of passionflower, especially Passiflora edulis (purple granadilla) or P. quadrangularis (giant granadilla)
  • put a dampener on — To put a dampener on something means the same as to put a damper on it.
  • put on a pedestal — an architectural support for a column, statue, vase, or the like.
  • put one's hand to — the terminal, prehensile part of the upper limb in humans and other primates, consisting of the wrist, metacarpal area, fingers, and thumb.
  • pyroligneous acid — a yellowish, acidic, water-soluble liquid, containing about 10 percent acetic acid, obtained by the destructive distillation of wood: used for smoking meats.
  • quasi-independent — not influenced or controlled by others in matters of opinion, conduct, etc.; thinking or acting for oneself: an independent thinker.
  • quattuordecillion — a cardinal number represented in the U.S. by 1 followed by 45 zeros, and in Great Britain by 1 followed by 84 zeros.
  • quick on the draw — having fast reflexes
  • radioluminescence — luminescence induced by nuclear radiation.
  • raynaud's disease — a vascular disorder of unknown cause, characterized by recurrent episodes of blanching and numbness of the fingers and toes and sometimes the tip of the nose and ears, usually triggered by stress or exposure to cold.
  • recreation ground — an open space for public recreation, esp one in a town, with swings and slides, etc, for children
  • recreational drug — drug taken for pleasure
  • recurring decimal — Mathematics. repeating decimal.
  • reduction formula — a formula, such as sin (90° ± A) = cos A, expressing the values of a trigonometric function of any angle greater than 90° in terms of a function of an acute angle
  • regulated tenancy — (in Britain) the letting of a dwelling by a nonresident private landlord, usually at a registered fair rent, from which the landlord cannot evict the tenant without a possession order from a court
  • rhodope mountains — a mountain range in SE Europe, in the Balkan Peninsula extending along the border between Bulgaria and Greece. Highest peak: Golyam Perelik (Bulgaria), 2191 m (7188 ft)
  • ring-tailed lemur — a Madagascan prosimian primate, Lemur catta, with a long black and white ringed tail
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