18-letter words containing r, o, s
- calliper compasses — an instrument for measuring internal or external dimensions, consisting of two steel legs hinged together
- cambrian mountains — a mountain range in Wales, extending from Carmarthenshire in the S to Denbighshire in the N. Highest peak: Aran Fawddwy, 891 m (2970 ft)
- camp david accords — a peace treaty between Israel and Egypt issuing from talks at Camp David between Egyptian President Sadat, Israeli Prime Minister Begin, and the host, U.S. President Carter: signed in 1979.
- cape breton island — an island off SE Canada, in NE Nova Scotia, separated from the mainland by the Strait of Canso: its easternmost point is Cape Breton. Pop: 132 298 (2006). Area: 10 280 sq km (3970 sq miles)
- carbonic anhydrase — an enzyme in blood cells that catalyses the decomposition of carbonic acid into carbon dioxide and water, facilitating the transport of carbon dioxide from the tissues to the lungs
- carcinoid syndrome — the systemic effects, including flushing, palpitations, diarrhea, and cramps, resulting from increased blood levels of serotonin secreted by a carcinoid.
- carisbrooke castle — a castle near Newport on the Isle of Wight: Charles I was held prisoner here from 1647 until his execution in 1649
- carolina jessamine — a vine, Gelsemium sempervirens, of the southern U.S. and Central America, of the logania family, having glossy, lance-shaped leaves and fragrant yellow flowers: the state flower of South Carolina.
- cartilaginous fish — any fish of the class Chondrichthyes, including the sharks, skates, and rays, having a skeleton composed entirely of cartilage
- cash-for-questions — of, involved in, or relating to a scandal in which some MPs were accused of accepting bribes to ask particular questions in Parliament
- cassiopeia's chair — the five brightest stars in the constellation Cassiopeia that seem to form the shape of a W or M
- castration complex — an unconscious fear of having one's genitals removed, as a punishment for wishing to have sex with a parent
- cat's cry syndrome — a complex of congenital malformations in human infants caused by a chromosomal aberration and in which the infant emits a mewing cry.
- catalogue raisonne — a descriptive catalogue, esp one covering works of art in an exhibition or collection
- catastrophe theory — a mathematical theory that classifies surfaces according to their form
- catch one's breath — When you catch your breath while you are doing something energetic, you stop for a short time so that you can start breathing normally again.
- catherine of siena — Saint. 1347–80, Italian mystic and ascetic; patron saint of the Dominican order. Feast day: April 29
- cathode dark space — Crookes dark space.
- cauliflower cheese — a dish of cauliflower with a cheese sauce, eaten hot
- cauliflower fungus — a large edible white to yellowish cauliflowerlike mushroom, Sparassis radicata, widely distributed in North America.
- center of symmetry — a point within a crystal through which any straight line extends to points on opposite surfaces of the crystal at equal distances.
- centralized school — a public school formed from the pupils and teachers of a number of discontinued smaller schools, especially in a rural district.
- centre of pressure — the point in a body at which the resultant pressure acts when the body is immersed in a fluid
- cesarean (section) — a surgical operation for delivering a baby by cutting through the mother's abdominal and uterine walls
- chagos archipelago — group of islands in the Indian Ocean 1,180 mi (1,899 km) northeast of Mauritius, comprising the British Indian Ocean Territory: chief island, Diego Garcia
- chamber of horrors — a room, for example in a waxworks, containing objects, images or representations of people or scenes that are believed likely to frighten or horrify visitors
- character disorder — a disorder characterized by socially undesirable behavior, as poor control of impulses or inability to maintain close emotional relationships, and by absence of anxiety or guilt.
- charge of quarters — a member of the armed forces who handles administration in his or her unit, esp after duty hours
- chartered surveyor — (in Britain) a surveyor who is registered with the Royal Institution of Chartered Surveyors as having the qualifications, training, and experience to satisfy their professional requirements
- chew someone's ear — to reprimand severely
- children of israel — the Jews; Hebrews
- chinese gooseberry — kiwi (sense 2)
- chinese revolution — the overthrow of the last Manchu emperor and the establishment of a republic in China (1911–12)
- chinese watermelon — a tropical Asian vine, Benincasa hispida, of the gourd family, having a brown, hairy stem, large, solitary, yellow flowers, and white, melonlike fruit.
- chord of the sixth — sixth chord.
- chrétien de troyes — 12th century, French poet, who wrote the five Arthurian romances Erec; Cligès; Lancelot, le chevalier de la charette; Yvain, le chevalier au lion; and Perceval, le conte del Graal (?1155–?1190), the first courtly romances
- christian brothers — a religious congregation of laymen founded in France in 1684 for the education of the poor
- christian democrat — a member or supporter of a Christian Democratic party
- christian endeavor — an organization of young people of various evangelical Protestant churches, formed in 1881 to promote Christian principles and service.
- christian reformed — of or relating to a Protestant denomination (Christian Reformed Church) organized in the U.S. in 1857 by groups that had seceded from the Dutch Reformed Church.
- christmas shopping — shopping especially for Christmas presents, but also for Christmas food and drink, and all the other things required over the Christmas period.
- christmas stocking — A Christmas stocking is a long sock which children hang up on Christmas Eve. During the night, parents fill the stocking with small presents.
- christopher sholes — Christopher Latham [ley-thuh m,, -th uh m] /ˈleɪ θəm,, -ðəm/ (Show IPA), 1819–90, U.S. inventor of the typewriter.
- chromatic semitone — the pitch difference between one note and its sharpened or flattened equivalent
- chronic alcoholism — long-term alcohol addiction
- chronic bronchitis — persistent respiratory disease
- chronostratigraphy — The branch of geology concerned with establishing the absolute ages of strata.
- church of scotland — the established church in Scotland, Calvinist in doctrine and Presbyterian in constitution
- cigar-store indian — a wooden statue of an American Indian, traditionally displayed at the entrance of cigar stores.
- circular dichroism — selective absorption of one of the two possible circular polarizations of light.