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Clement VI, pope

(Encyclopedia)Clement VI, 1291–1352, pope (1342–52), a Frenchman named Pierre Roger; successor of Benedict XII. His court was at Avignon. He had been archbishop of Sens, archbishop of Rouen, and cardinal (1338)...

Turkish language

(Encyclopedia)Turkish language, member of the Turkic subdivision of the Altaic subfamily of the Ural-Altaic family of languages (see Uralic and Altaic languages). Turkish is the official language of Turkey and one ...

gall, in botany

(Encyclopedia)gall, abnormal growth, or hypertrophy, of plant tissue produced by chemical or mechanical (e.g., the rubbing together of two branches) irritants or hormones. Chemical irritants are released by parasit...

horsetail

(Encyclopedia)horsetail, any plant of the genus Equisetum [Lat.,=horse bristle], the single surviving genus of a large group (Equisetophyta) of primitive vascular plants. Like the ferns and club mosses, relatives o...

cerebellum

(Encyclopedia)cerebellum sĕrˌəbĕlˈəm [key], portion of the brain that coordinates movements of voluntary (skeletal) muscles. It contains about half of the brain's neurons, but these particular nerve cells are...

Bryophyta

(Encyclopedia)Bryophyta brīˈəfīˌtə, brīˌəfīˈtə [key], division of green land plants that includes the mosses (class Bryopsida), the liverworts (Marchantiopsida), and the hornworts (Anthocerotopsida). Th...

cactus

(Encyclopedia)cactus, any plant of the family Cactaceae, a large group of succulents found almost entirely in the New World. A cactus plant is conspicuous for its fleshy green stem, which performs the functions of ...

wood

(Encyclopedia)CE5 Wood A. Cross section of a woody stem B. Enlarged view, showing xylem, phloem, and cambium wood, botanically, the xylem tissue that forms the bulk of the stem of a woody plant. Xylem conducts ...

auxin

(Encyclopedia)auxin ôkˈsĭn [key], plant hormone that regulates the amount, type, and direction of plant growth. Auxins include both naturally occurring substances and related synthetic compounds that have simila...

Missouri River basin project

(Encyclopedia)Missouri River basin project, comprehensive plan authorized in 1944 for the coordinated development of water resources of the Missouri River and its tributaries, draining an area of c.513,300 sq mi (1...

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