18-letter words containing e, c, h, o, a
- 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.
- considered harmful — (programming, humour) A type of phrase based on the title of Edsger W. Dijkstra's famous note in the March 1968 Communications of the ACM, "Goto Statement Considered Harmful", which fired the first salvo in the structured programming wars. Amusingly, the ACM considered the resulting acrimony sufficiently harmful that it will (by policy) no longer print articles taking so assertive a position against a coding practice. In the ensuing decades, a large number of both serious papers and parodies bore titles of the form "X considered Y". The structured-programming wars eventually blew over with the realisation that both sides were wrong, but use of such titles has remained as a persistent minor in-joke.
- continental shield — any of the large, low-lying areas in the Earth's crust that are composed of Precambrian crystalline rocks
- 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.
- 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
- countertherapeutic — Working against a therapy.
- cranial osteopathy — osteopathy that focuses on the cranium and the spine
- creatine phosphate — phosphocreatine.
- crystal microphone — a microphone that uses a piezoelectric crystal to convert sound energy into electrical energy
- cytoarchitectonics — Cytoarchitecture.
- death by chocolate — a very rich type of chocolate dessert or cake
- 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.
- 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
- diatomaceous earth — an unconsolidated form of diatomite
- dichloracetic acid — a highly corrosive acid. Formula: C2H2Cl2O2
- 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.
- diphosphoglycerate — an ester of phosphoric acid and glyceric acid that occurs in the blood and that promotes the release of hemoglobin-bound oxygen.
- diplomatic shuttle — a series of diplomatic visits to other states made by an official, such as an ambassador or envoy
- dispatch documents — documents sent with a parcel, etc, detailing information such as contents, delivery address, etc
- dodecadodecahedral — Having the form of a dodecadodecahedron.
- dodecadodecahedron — (geometry) A nonconvex polyhedron with twenty-four faces, thirty vertices, and sixty edges.
- double achievement — a representation of the arms of a husband beside those of his wife such that a difference of rank between them is shown.
- drinking chocolate — sweetened cocoa powder
- each and every one — all
- echoencephalograph — a device that employs reflected ultrasonic waves to examine the position of brain structures.
- economic geography — a branch of geography that deals with the relation of physical and economic conditions to the production and utilization of raw materials and their manufacture into finished products.
- eggshell porcelain — a type of very thin translucent porcelain originally made in China
- electrocardiograph — A machine used for electrocardiography.
- electrophotography — Any of several methods of photocopying in which an image is created and then transferred between surfaces using static electricity.
- electrotherapeutic — Relating to electrotherapeutics.
- epicycloidal wheel — one of the planetary gears of an epicyclic train
- ethnomusicological — Relating to or pertaining to ethnomusicology.
- ethnopsychological — Relating to ethnopsychology.
- 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).
- exchange programme — an arrangement in which people from different countries visit each other's country, perhaps to strengthen links between them or to improve foreign language skills
- farm the long acre — to graze cows on the verge of a road
- fifth monarchy men — (during the Commonwealth in the 17th century) a militant sect of Puritans who identified the fifth monarchy with the millennial reign of Christ and who believed they should help to inaugurate that reign by force.
- fischer von erlach — Johann Bernhard [yaw-hahn bern-hahrt] /ˈyɔ hɑn ˈbɛrn hɑrt/ (Show IPA), 1656–1723, Austrian architect.
- fly in the face of — to move through the air using wings.
- fourth commandment — “Remember the sabbath day, to keep it holy”: fourth of the Ten Commandments.