Columbia Encyclopedia

Search results

500 results found

DNA fingerprinting

(Encyclopedia)DNA fingerprinting or DNA profiling, any of several similar techniques for analyzing and comparing DNA from separate sources, used especially in law enforcement to identify suspects from hair, blood, ...

Gregory I, Saint

(Encyclopedia)Gregory I, Saint (Saint Gregory the Great), c.540–604, pope (590–604), a Roman; successor of Pelagius II. A Doctor of the Church, he was distinguished for his spiritual and temporal leadership. Hi...

Normans

(Encyclopedia)Normans, designation for the Northmen, or Norsemen, who conquered Normandy in the 10th cent. and adopted Christianity and the customs and language of France. Abandoning piracy and raiding, they adopte...

muscular dystrophy

(Encyclopedia)muscular dystrophy dĭsˈtrōfē [key], any of several inherited diseases characterized by progressive wasting of the skeletal muscles. There are five main forms of the disease. They are classified ac...

climate

(Encyclopedia)climate, average condition of the atmosphere near the earth's surface over a long period of time, taking into account temperature, precipitation (see rain), humidity, wind, barometric pressure, and ot...

black hole

(Encyclopedia)black hole, in astronomy, celestial object of such extremely intense gravity that it attracts everything near it and in some instances prevents everything, including light, from escaping. The term was...

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...

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....

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 ...