18-letter words containing o, a, r
- critical constants — the physical constants that express the properties of a substance in its critical state
- crookes dark space — the dark space between the cathode glow and the negative glow in a vacuum tube, occurring when the pressure is low.
- crookes radiometer — a type of radiometer consisting of an evacuated glass bulb containing a set of lightweight vanes, each blackened on one side. The vanes are mounted on a vertical axis and revolve when light, or other radiant energy, falls on them
- cross-disciplinary — linking two or more fields of study
- crude oil desalter — A crude oil desalter is equipment which removes inorganic salts from crude oil, using chemical or electrostatic separation.
- crude oil fraction — A crude oil fraction is a component of crude oil, which has its own particular molecular composition, weight, and boiling point.
- crystal microphone — a microphone that uses a piezoelectric crystal to convert sound energy into electrical energy
- crystal oscillator — a clear, transparent mineral or glass resembling ice.
- cultural diffusion — act of diffusing; state of being diffused.
- cultural sociology — the study of the origins and development of societal institutions, norms, and practices.
- cumbrian mountains — a mountain range in NW England, in Cumbria. Highest peak: Scafell Pike, 977 m (3206 ft)
- cumulative scoring — a method of scoring in which the score of a partnership is taken as the sum of their scores on all hands played.
- curvature of field — a monochromatic aberration of a lens or other optical system in which the focal surface is curved, the refracted image of an object oriented perpendicular to the axis of the lens lying on a curved surface rather than in a plane perpendicular to the axis.
- curvature of space — (in relativity) a property of space near massive bodies in which their gravitational field causes light to travel along curved paths.
- customer relations — Customer relations are the relationships that a business has with its customers and the way in which it treats them.
- cutthroat contract — a form of contract bridge for four persons in which partners are decided by the bidding.
- cyclopean concrete — concrete containing stones larger than 6 inches (15 cm).
- cyrano de bergerac — Savinien (savinjɛ̃). 1619–55, French writer and soldier, famous as a duellist and for his large nose. He became widely known through the verse drama Cyrano de Bergerac (1897) by Edmond Rostand
- cytoarchitectonics — Cytoarchitecture.
- dangerous offender — an offender who is deemed by a court of law to be likely to engage in further violent conduct, and who thus becomes eligible for an indefinite prison sentence
- david lloyd george — David, 1st Earl of Dwyfor [doo-vawr] /ˈdu vɔr/ (Show IPA), 1863–1945, British statesman: prime minister 1916–22.
- de bruijn notation — (language) A variation of lambda notation for specifying functions using numbers instead of names to refer to formal parameters. A reference to a formal parameter is a number which gives the number of lambdas (written as \ here) between the reference and the lambda which binds the parameter. E.g. the function \ f . \ x . f x would be written \ . \ . 1 0. The 0 refers to the innermost lambda, the 1 to the next etc. The chief advantage of this notation is that it avoids the possibility of name capture and removes the need for alpha conversion.
- de-differentiation — a process by which structures or behaviors that were specialized for a specific function lose their specialization and become simplified or generalized.
- dead as a doornail — completely dead
- dead-letter office — an office where undeliverable letters were taken for storage
- deanthropomorphism — the ridding of philosophy or religion of anthropomorphic beliefs and doctrines.
- dear john (letter) — a letter from one's fiancée or girlfriend breaking off an engagement or love affair, or from one's wife asking for a divorce
- decachlorobiphenyl — (organic compound) The fully chlorinated polychlorinated biphenyl containing ten chlorine atoms.
- dechristianization — The act of dechristianizing; the systematic removal of Christianity or Christian elements.
- declaration of war — a formal statement made by one country to another that a state of war now exists between them
- decompartmentalize — to remove excessive compartmentalization from (an organization)
- defense calculator — IBM 701
- demilitarized zone — an area from which military presence or function has been removed
- democratic deficit — any situation in which there is believed to be a lack of democratic accountability and control over the decision-making process
- demorgan's theorem — (logic) A logical theorem which states that the complement of a conjunction is the disjunction of the complements or vice versa. In symbols: not (x and y) = (not x) or (not y) not (x or y) = (not x) and (not y) E.g. if it is not the case that I am tall and thin then I am either short or fat (or both). The theorem can be extended to combinations of more than two terms in the obvious way. The same laws also apply to sets, replacing logical complement with set complement, conjunction ("and") with set intersection, and disjunction ("or") with set union. A (C) programmer might use this to re-write if (!foo && !bar) ... as if (!(foo || bar)) ... thus saving one operator application (though an optimising compiler should do the same, leaving the programmer free to use whichever form seemed clearest).
- departmental store — a department store.
- departure platform — a raised area at a railway station from which passengers can board trains prior to their departing
- depository library — a library designated by law to receive without charge all or a selection of the official publications of a government.
- dermot macmurrough — ?1110–71, king of Leinster, who, by enlisting the support of the English to win back his kingdom, was responsible for the English conquest of Ireland
- determinate growth — growth of a plant stem that is terminated early by the formation of a bud
- dia de los muertos — Day of the Dead.
- diaminofluorescein — (organic compound) A fluorescein into which two amino groups have been substituted.
- diamondback turtle — any edible North American terrapin of the genus Malaclemys, esp M. terrapin, occurring in brackish and tidal waters and having diamond-shaped markings on the shell: family Emydidae
- diastereoisomerism — (chemistry) Any form of stereoisomerism other than enantiomerism.
- diatomaceous earth — an unconsolidated form of diatomite
- dichloracetic acid — a highly corrosive acid. Formula: C2H2Cl2O2
- dictionary catalog — a library catalog having all its entries, including authors, titles, subjects, etc., in one general alphabetical sequence.
- digital switchover — the process of changing the method of transmitting television from analogue to digital format
- dihydrotachysterol — a white, crystalline, water-insoluble sterol, C 28 H 46 O, derived from ergosterol: used chiefly in the treatment of hypoparathyroidism.
- diphosphoglycerate — an ester of phosphoric acid and glyceric acid that occurs in the blood and that promotes the release of hemoglobin-bound oxygen.