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tense

(Encyclopedia)tense [O.Fr., from Lat.,=time], in the grammar of many languages, a category of time distinctions expressed by any conjugated form of a verb. In Latin inflection the tense of a verb is indicated by a ...

xenon

(Encyclopedia)xenon zēˈnŏn [key] [Gr.,=strange], gaseous chemical element; symbol Xe; at. no. 54; at. wt. 131.293; m.p. −111.9℃; b.p. −107.1℃; density 5.86 grams per liter at STP; valence usually 0. Xeno...

brittlestar

(Encyclopedia)brittlestar, common name for echinoderms belonging to the class Ophiuroidea. The name is derived from their habit of breaking off arms as a means of defense. New arms are easily regenerated. They are ...

termite

(Encyclopedia)termite or white ant, common name for a soft-bodied social insect of the infraorder Isoptera. Originally classified in as a separate order, termites are genetically related to cockroaches and are now ...

Falun Gong

(Encyclopedia)Falun Gong dä-fä [key], movement promoting physical and spiritual well-being that became widespread China in the 1990s. Founded in 1992 by Li Hongzhi (1951?–), a former Changchun grain clerk, it c...

hydrogen chloride

(Encyclopedia)hydrogen chloride, chemical compound, HCl, a colorless, poisonous gas with an unpleasant, acrid odor. It is very soluble in water and readily soluble in alcohol and ether. It fumes in moist air. It is...

hydrolysis

(Encyclopedia)hydrolysis hīdrŏlˈĭsĭs [key], chemical reaction of a compound with water, usually resulting in the formation of one or more new compounds. The most common hydrolysis occurs when a salt of a weak ...

hydroxide

(Encyclopedia)hydroxide hīdrŏkˈsīd [key], chemical compound that contains the hydroxyl (−OH) radical. The term refers especially to inorganic compounds. Organic compounds that have the hydroxyl radical as a f...

histidine

(Encyclopedia)CE5 histidine hĭsˈtĭdēn [key], organic compound, one of the 22 α-amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. Histidine is the direct pr...

mantid

(Encyclopedia)mantid or mantis, name applied to the large, slender, slow-moving, winged insects of the family Mantidae in the order Mantodea. Predatory insects, mantids have strong, elongate, spiny front legs, used...