18-letter words containing h, e, t
- continuation sheet — (in a document) a page that continues from the one before it, containing similar information
- 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.
- cordless telephone — a portable battery-powered telephone with a short-range radio link to a fixed base unit
- 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
- 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
- counter-hypothesis — a proposition, or set of propositions, set forth as an explanation for the occurrence of some specified group of phenomena, either asserted merely as a provisional conjecture to guide investigation (working hypothesis) or accepted as highly probable in the light of established facts.
- countertherapeutic — Working against a therapy.
- court of exchequer — (formerly) an English civil court where Crown revenue cases were tried
- 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
- cut one's eyeteeth — to become experienced or sophisticated
- cut one's teeth on — to use at an early age or stage
- cyclic pitch lever — a lever in a helicopter to change the angle of attack of individual rotor blades, causing the helicopter to move forwards, backwards, or sideways
- 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.
- danish west indies — the former possession of Denmark in the W Lesser Antilles, sold to the US in 1917
- deadweight tonnage — the capacity in long tons of cargo, passengers, fuel, stores, etc. (deadweight tons) of a vessel: the difference between the loaded and light displacement tonnage of the vessel.
- 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 by chocolate — a very rich type of chocolate dessert or cake
- 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).
- dendrochronologist — One who carries out dendrochronology.
- 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
- desktop publishing — Desktop publishing is the production of printed materials such as newspapers and magazines using a desktop computer and a laser printer, rather than using conventional printing methods. The abbreviation DTP is also used.
- 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.
- diethylstilbestrol — a nonsteroidal synthetic estrogen, C 18 H 20 O 2 , used in medicine chiefly in the treatment of menopausal symptoms and in animal feeds for chemical caponization: formerly used during pregnancy for the prevention of miscarriage but discontinued owing to its association with an increased risk of vaginal and cervical cancers in women having had fetal exposure. Abbreviation: DES.
- digital humanities — (used with a singular verb) the study of literature, philosophy, etc., as facilitated by computer technology or digital media: Digital humanities uses data analysis to find patterns in large bodies of text. the set of methodologies used in such scholarship.
- digital switchover — the process of changing the method of transmitting television from analogue to digital format
- digital technology — the branch of scientific or engineering knowledge that deals with the creation and practical use of digital or computerized devices, methods, systems, etc.: advances in digital technology.
- dihydrotachysterol — a white, crystalline, water-insoluble sterol, C 28 H 46 O, derived from ergosterol: used chiefly in the treatment of hypoparathyroidism.
- dimethyl sulfoxide — DMSO.
- dimethylsulphoxide — a colourless odourless liquid substance used as a solvent and in medicine as an agent to improve the penetration of drugs applied to the skin. Formula: (CH3)2SO
- 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