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17-letter words containing d, u, r

  • muscle dysmorphia — a mental disorder primarily affecting males, characterized by obsessions about a perceived lack of muscularity, leading to compulsive exercising, use of anabolic steroids, etc. Compare body dysmorphic disorder.
  • musical interlude — an interval in a play, event or occasion during which music is played
  • mustard and cress — Mustard and cress is very young mustard plants and cress plants grown together and eaten in salad.
  • naked singularity — an infinitely dense point mass without a surrounding black hole
  • narrow-shouldered — having shoulders which do not extend very far from the neck; not broad-shouldered
  • nasolacrimal duct — a membranous canal extending from the lacrimal sac to the nasal cavity, through which tears are discharged into the nose.
  • 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.
  • nichiren buddhism — a doctrine of salvation based on the Lotus Sutra.
  • non-subordination — the act of placing in a lower rank or position: The refusal to allow women to be educated was part of society's subordination of women to men.
  • nonproductiveness — The quality of being nonproductive.
  • nonunderstandable — Not understandable.
  • northern studfish — See under studfish.
  • noun pre-modifier — a noun that occurs before and modifies another noun, as toy in toy store or tour in tour group.
  • 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
  • number three wood — spoon (def 5).
  • 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
  • odour of sanctity — sanctimoniousness
  • old south arabian — a group of four closely related Semitic languages, having a writing system and used from about the eighth to the fifth centuries b.c. in the southern part of Arabia.
  • old wives' summer — a period of fine, summerlike weather occurring in Europe in autumn.
  • on (or off) duty — at (or temporarily relieved from) one's work, duty, etc.
  • order of business — a task assigned or to be dealt with: Our first order of business is to reduce expenses.
  • orfeo ed euridice — an opera (1762), with music by Christoph Willibald von Gluck.
  • out of this world — the earth or globe, considered as a planet.
  • outside broadcast — An outside broadcast is a radio or television programme that is not recorded or filmed in a studio, but in another building or in the open air.
  • paratungstic acid — an oxyacid acid of tungsten. Formula: H10W12O14
  • performance drugs — the drugs that are taken illegally by athletes to enhance their sporting performance
  • period-revolution — a rather large interval of time that is meaningful in the life of a person, in history, etc., because of its particular characteristics: a period of illness; a period of great profitability for a company; a period of social unrest in Germany.
  • periodic function — a function of a real or complex variable that is periodic.
  • piccadilly circus — a traffic circle and open square in W London, England: theater and amusement center.
  • pittsburg landing — a village in SW Tennessee, on the Tennessee River: battle of Shiloh in 1862.
  • plastics industry — the industry that makes plastics
  • 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.
  • police procedural — a mystery novel, film, or television drama that deals realistically with police work.
  • 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 bromide — a white, crystalline, water-soluble powder, KBr, having a bitter saline taste: used chiefly in the manufacture of photographic papers and plates, in engraving, and in medicine as a sedative.
  • powder metallurgy — the art or science of manufacturing useful articles by compacting metal and other powders in a die, followed by sintering.
  • prelingually deaf — deaf from birth or having acquired deafness before learning to speak
  • premiere danseuse — the leading female dancer in a ballet company.
  • prescription drug — medication available only on doctor's instruction
  • pressure altitude — the altitude for a given pressure in a standard atmosphere, such as that registered by a pressure altimeter.
  • 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
  • printing industry — the industry engaged in the business of producing printed matter
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