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furnace

(Encyclopedia)furnace, enclosed space for the burning of fuel. There are many kinds of furnaces, the type depending upon the fuel and the use to which the heat produced within it is put. Most familiar are the furna...

chloride

(Encyclopedia)chloride klōrˈīd, klôrˈ– [key], chemical compound containing chlorine. Most chlorides are salts that are formed either by direct union of chlorine with a metal or by reaction of hydrochloric ac...

thyroid gland

(Encyclopedia)CE5 Thyroid gland thyroid gland, endocrine gland, situated in the neck, that secretes hormones necessary for growth and proper metabolism. It consists of two lobes connected by a narrow segment ca...

lanthanide series

(Encyclopedia)lanthanide series, a series of metallic elements, included in the rare-earth metals, in Group 3 of the periodic table. Members of the series are often called lanthanides, although lanthanum (atomic nu...

lava

(Encyclopedia)lava läˈvə [key], molten rock that erupts on the earth's surface, either on land or under the ocean, by a volcano or through a fissure. It solidifies into igneous rock that is also called lava. Bef...

corticosteroid drug

(Encyclopedia)corticosteroid drug kôrˌtəkōstârˈoid [key], any one of several synthetic or naturally occurring substances with the general chemical structure of steroids. They are used therapeutically to mimic...

pearl, gem

(Encyclopedia)pearl, hard, rounded secretion formed inside the shell of certain mollusks, used as a gem. It is secreted by the epithelial cells of the mantle, a curtain of tissue between the shell and body mass, an...

molybdenum

(Encyclopedia)molybdenum məlĭbˈdənəm [key] [Gr.,=leadlike], metallic chemical element; symbol Mo; at. no. 42; at. wt. 95.96; m.p. about 2,617℃; b.p. about 4,612℃; sp. gr. 10.22 at 20℃; valence +2, +3, +4...

arum

(Encyclopedia)CE5 Jack-in-the-pulpit, Arisaema triphyllum, a member of the arum family arum, common name for the Araceae, a plant family mainly composed of species of herbaceous terrestrial and epiphytic plants...

soap

(Encyclopedia)soap, a cleansing agent. It cleanses by lowering the surface tension of water, by emulsifying grease, and by absorbing dirt into the foam. Ancient peoples are believed to have employed wood ashes and ...