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pheromones

(Encyclopedia)pheromones, any of a variety of substances, secreted by many animal species, that alter the behavior of individuals of the same species. Sex attractant pheromones, secreted by a male or female to attr...

Coptos

(Encyclopedia)Coptos kŏpˈtəs [key], ancient city of Egypt, on the right bank of the Nile, c.27 mi (43 km) N of modern Luxor. Remains of the Temple of Min, patron god of Coptos, have been found there as well as r...

corns and calluses

(Encyclopedia)corns and calluses, thickenings of the outer layer of skin where there is irritation or constant pressure. Corns are cone-shaped with their points protruding into the dermis, or inner layer of skin. T...

Comyn, John (Red Comyn), d. 1306, Scottish nobleman

(Encyclopedia)Comyn, John, d. 1306, Scottish nobleman. He was called the Red Comyn, to distinguish him from his father, the Black Comyn. Aiding his uncle, John de Baliol, in the struggle against Edward I, he was fo...

dermatitis

(Encyclopedia)dermatitis dûrˌmətīˈtĭs [key], nonspecific irritation of the skin. The causative agent may be a bacterium, fungus, or parasite; it can also be a foreign substance, known as an allergen. Contact ...

Chelsea ware

(Encyclopedia)Chelsea ware, chinaware made in the mid-18th cent. at a factory in Chelsea, London. The earliest specimens extant are dated 1745 and have the potter's mark of a triangle and the word Chelsea. Nicholas...

dragon's blood

(Encyclopedia)dragon's blood, name for a red resin obtained from a number of different plants. It was held by early Greeks, Romans, and Arabs to have medicinal properties; Dioscorides and other early writers descri...

Geneva Conventions

(Encyclopedia)Geneva Conventions, series of treaties signed (1864–1949) in Geneva, Switzerland, providing for humane treatment of combatants and civilians in wartime. The first convention, signed by 16 nations, c...

gingivitis

(Encyclopedia)gingivitis jĭnˌjəvīˈtĭs [key], inflammation of the gums. It may be acute, subacute, chronic, or recurrent. The gums usually become red, swollen, and spongy, and bleed easily. Chronic gingivitis ...

Flaming Gorge Dam

(Encyclopedia)Flaming Gorge Dam, in a deep canyon of the Green River, NE Utah; built 1958–63 by the U.S. Bureau of Reclamation as a major unit in the Colorado River storage project. The dam regulates the flow of ...
 

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