18-letter words containing t, h, r, e, a, d
- 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.
- 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.
- 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.
- electric discharge — electricity emitted
- electrocardiograph — A machine used for electrocardiography.
- established church — a Church that is officially recognized as a national institution, esp the Church of England
- euclid's algorithm — (algorithm) (Or "Euclidean Algorithm") An algorithm for finding the greatest common divisor (GCD) of two numbers. It relies on the identity gcd(a, b) = gcd(a-b, b) To find the GCD of two numbers by this algorithm, repeatedly replace the larger by subtracting the smaller from it until the two numbers are equal. E.g. 132, 168 -> 132, 36 -> 96, 36 -> 60, 36 -> 24, 36 -> 24, 12 -> 12, 12 so the GCD of 132 and 168 is 12. This algorithm requires only subtraction and comparison operations but can take a number of steps proportional to the difference between the initial numbers (e.g. gcd(1, 1001) will take 1000 steps).
- every now and then — from time to time; occasionally
- fall to the ground — (of a plan, theory, etc) to be rendered invalid, esp because of lack of necessary information
- farmer in the dell — a game, accompanied by a song with several verses, in which one person, designated as the farmer, occupies the center of a circle of persons and is joined in the circle by other players designated as wife, child, nurse, cat, rat, and cheese, these then leaving the circle in order except for the one designated as cheese, who is left standing alone in the circle at the end.
- feast of orthodoxy — a solemn festival held on the first Sunday of Lent (Orthodoxy Sunday) commemorating the restoration of the use of icons in the church (a.d. 842) and the triumph over all heresies.
- feldenkrais method — a system of gentle movements that promote flexibility, coordination, and self-awareness
- fourth commandment — “Remember the sabbath day, to keep it holy”: fourth of the Ten Commandments.
- gas-discharge tube — any tube in which an electric discharge takes place through a gas
- get the upper hand — gain advantage
- give sb their head — If you give someone their head, you allow them to do what they want to do, without trying to advise or stop them.
- gladden sb's heart — If you say that something gladdens someone's heart, you mean that it makes them feel pleased and hopeful.
- grandfather clause — U.S. History. a clause in the constitutions of some Southern states after 1890 intended to permit whites to vote while disfranchising blacks: it exempted from new literacy and property qualifications for voting those men entitled to vote before 1867 and their lineal descendants.
- handkerchief table — corner table.
- handlebar mustache — A handlebar mustache is a long thick mustache with curled ends.
- harnessed antelope — any African antelope of the genus Tragelaphus, especially the bushbuck, having the body marked with white stripes and spots that resemble a harness, and, in the male, long, gently spiraling horns.
- haud your wheesht! — be silent! hush!
- have words with sb — If one person has words with another, or if two or more people have words, they have a serious discussion or argument, especially because one has complained about the other's behaviour.
- headquarters staff — the people who work at the headquarters of an organization
- hearts and flowers — maudlin sentimentality: The play is a period piece, full of innocence abused and hearts and flowers.
- heating degree-day — a degree-day below the standard temperature of 65°F or 19°C, used in estimating fuel consumption.
- hermaphrodite brig — a two-masted sailing vessel, square-rigged on the foremast and fore-and-aft-rigged on the mainmast.
- heteroscedasticity — (statistics) The property of a series of random variables of 'not' every variable having the same finite variance.