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covenant

(Encyclopedia)covenant kŭvˈənənt [key], agreement entered into voluntarily by two or more parties to do or refrain from doing certain acts. In the Bible and in theology the covenant is the agreement or engageme...

chain reaction

(Encyclopedia)CE5 Chain reaction: A neutron (n) strikes the uranium nucleus (U-235), causing it to split into fission products A and B and release two neutrons. These neutrons can in turn cause further fissions....

dialysis

(Encyclopedia)dialysis dīălˈĭsĭs [key], in chemistry, transfer of solute (dissolved solids) across a semipermeable membrane. Strictly speaking, dialysis refers only to the transfer of the solute; transfer of t...

etching

(Encyclopedia)etching, the art of engraving with acid on metal; also the print taken from the metal plate so engraved. In hard-ground etching the plate, usually of copper or zinc, is given a thin coating or ground ...

embryo screening

(Encyclopedia)embryo screening, procedure (see genetic testing) in which a single cell is removed from an embryo two or three days after it has been conceived through in vitro fertilization and tested for genetic a...

spring, in geology

(Encyclopedia)spring, in geology, natural flow of water from the ground or from rocks, representing an outlet for the water that has accumulated in permeable rock strata underground. Some of the water that falls as...

nosebleed

(Encyclopedia)nosebleed, nasal hemorrhage occurring as the result of local injury or disturbance. Most nosebleeds are not serious and occur when one of the small veins of the septum (the partition between the nostr...

license

(Encyclopedia)license, in public law, permission by legal authority to engage in certain acts and also the document showing such permission. Some licenses are required for the protection of the public; they assure ...

Rugby, town, England

(Encyclopedia)Rugby, town (1991 pop. 59,039), Warwickshire, central England. An important railroad junction and engineering center, Rugby is the seat of one of England's most esteemed public schools. Rugby School w...

Rank, Otto

(Encyclopedia)Rank, Otto ôtˈō rängk [key], 1884–1937, Austrian psychoanalyst; one of Sigmund Freud's first and most valued pupils. He early employed Freudian techniques to clarify the underlying significance ...