18-letter words containing a, r, h, t
- collection charges — the charges levied to cover expenses for the collection of debt
- colour photography — the art or process of taking and developing photographs in colour
- combustion chamber — an enclosed space in which combustion takes place, such as the space above the piston in the cylinder head of an internal-combustion engine or the chambers in a gas turbine or rocket engine in which fuel and oxidant burn
- come back to earth — to return to reality from a fantasy or daydream
- come the raw prawn — to attempt deception
- commercial attache — an attaché in an embassy or legation representing the commercial interests of his or her country.
- comparative method — a body of procedures and criteria used by linguists to determine whether and how two or more languages are related and to reconstruct forms of their hypothetical parent language.
- congregate housing — a type of housing in which each individual or family has a private bedroom or living quarters but shares with other residents a common dining room, recreational room, or other facilities.
- connected subgraph — (mathematics) A connected graph consisting of a subset of the nodes and edges of some other graph.
- controllable-pitch — (of a marine or aircraft propeller) having blades whose pitch can be changed during navigation or flight; variable-pitch.
- conversation chair — an English chair of the 18th century designed to be straddled facing the back of the chair with the elbows resting on the crest rail: an English imitation of the voyeuse.
- copper naphthenate — a green salt, soluble in benzene, used as an insecticide and a wood preservative, but harmless to plants.
- cornucopian thesis — the belief that, as long as science and technology continue to advance, growth can continue for ever because these new advances create new resources
- coronation chicken — a dish of cold cooked chicken in a mild creamy curry sauce
- corpus christi bay — a bay in S Texas, at the mouth of the Nueces River.
- corpuscular theory — the theory, originally proposed by Newton, and revived with the development of the quantum theory, that light consists of a stream of particles
- cot death syndrome — the unexplained sudden death of an infant during sleep
- countertherapeutic — Working against a therapy.
- cranial osteopathy — osteopathy that focuses on the cranium and the spine
- creatine phosphate — phosphocreatine.
- crested flycatcher — any of various tyrant flycatchers (esp. genus Myiarchus) with a prominent crest
- crested wheatgrass — a forage grass, Agropyron cristatum, native to Eurasia and grown in the Great Plains as pasturage, hay, and for erosion control.
- crystal microphone — a microphone that uses a piezoelectric crystal to convert sound energy into electrical energy
- cutthroat contract — a form of contract bridge for four persons in which partners are decided by the bidding.
- cytoarchitectonics — Cytoarchitecture.
- daisywheel printer — (printer) A kind of impact printer where the characters are arranged on the ends of the spokes of a wheel (resembling the petals on a daisy). The wheel (usually made of plastic) is rotated to select the character to print and then an electrically operated hammer mechanism bends the selected spoke forward slightly, sandwiching an ink ribbon between the character and the paper, as in a typewriter. One advantage of this arrangement over that of a typewriter is that different wheels may be inserted to produce different typefaces.
- 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
- death-valley curve — a curve on a graph showing how the capital of a new company plotted against time declines sharply as the venture capital is used up before income reaches predicted levels
- dechristianization — The act of dechristianizing; the systematic removal of Christianity or Christian elements.
- 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).
- depth-first search — (algorithm) A graph search algorithm which extends the current path as far as possible before backtracking to the last choice point and trying the next alternative path. Depth-first search may fail to find a solution if it enters a cycle in the graph. This can be avoided if we never extend a path to a node which it already contains. Opposite of breadth first search. See also iterative deepening.
- 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
- destruct mechanism — a mechanism that causes the destruction of a rocket or missile when activated
- determinate growth — growth of a plant stem that is terminated early by the formation of a bud
- devil's paintbrush — a perennial European hawkweed (Hieracium aurantiacum) with leafless flower stalks bearing a cluster of orange-red heads: now a common weed in N U.S. and Canada
- diatomaceous earth — an unconsolidated form of diatomite
- dichloracetic acid — a highly corrosive acid. Formula: C2H2Cl2O2
- dielectric heating — the heating of a nonconducting substance caused by dielectric loss when the material is placed in a variable electric field.
- 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.
- dimethyltryptamine — a hallucinogenic drug, C 12 H 16 N 2 , with an action of short duration. Abbreviation: DMT.
- diphosphoglycerate — an ester of phosphoric acid and glyceric acid that occurs in the blood and that promotes the release of hemoglobin-bound oxygen.
- diphtheria vaccine — a vaccine used to produce immunity against diphtheria
- discharge printing — a fabric-printing method in which the material is dyed and then certain areas are discharged so as to permit the original hue or its color replacement to act as a pattern against the colored ground.
- disenfranchisement — to disfranchise.
- division algorithm — the theorem that an integer can be written as the sum of the product of two integers, one a given positive integer, added to a positive integer smaller than the given positive integer. Compare Euclidean algorithm.
- drinking chocolate — sweetened cocoa powder
- drug on the market — Pharmacology. a chemical substance used in the treatment, cure, prevention, or diagnosis of disease or used to otherwise enhance physical or mental well-being.
- eastern hemisphere — the eastern part of the terrestrial globe, including Asia, Africa, Australia, and Europe.