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formula, in chemistry

(Encyclopedia)formula, in chemistry, an expression showing the chemical composition of a compound. Formulas of compounds are used in writing the equations (see chemical equations) that represent chemical reactions....

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...

amphibian, in aviation

(Encyclopedia)amphibian, in aviation: see seaplane. ...

amphibian, in zoology

(Encyclopedia)amphibian, in zoology, cold-blooded vertebrate animal of the class Amphibia. There are three living orders of amphibians: the frogs and toads (order Anura, or Salientia), the salamanders and newts (or...

Gault, in re

(Encyclopedia)Gault, in re ĭn rā gôlt [key], case decided in 1967 by the U.S. Supreme Court. Fifteen-year-old Gerald Gault had been found a delinquent by an Arizona juvenile court and sentenced to the state indu...

flag, in botany

(Encyclopedia)flag, common name for several plants belonging to the families Iridaceae and Araceae. See iris; arum. ...

flood, in hydrology

(Encyclopedia)flood, inundation of land by the rise and overflow of a body of water. Floods occur most commonly when water from heavy rainfall, from melting ice and snow, or from a combination of these exceeds the ...

fly, in zoology

(Encyclopedia)fly, name commonly used for any of a variety of winged insects, but properly restricted to members of the order Diptera, the true flies, which includes the housefly, gnat, midge, mosquito, and tsetse ...

joint, in anatomy

(Encyclopedia)joint, in anatomy, juncture between two bones. Some joints are immovable, e.g., those that connect the bones of the skull, which are separated merely by short, tough fibers of cartilage. Movable joint...

joint, in geology

(Encyclopedia)joint, in geology, fracture in rocks along which no appreciable movement has occurred (see fault). Nearly vertical, or sheet, joints that result from shrinkage during cooling are commonly found in ign...