Columbia Encyclopedia

Search results

500 results found

dispersion, in chemistry

(Encyclopedia)dispersion, in chemistry, mixture in which fine particles of one substance are scattered throughout another substance. A dispersion is classed as a suspension, colloid, or solution. Generally, the par...

division, in mathematics

(Encyclopedia)division, fundamental operation in arithmetic; the inverse of multiplication. Division may be indicated by the symbol ÷, as in 15 ÷ 3, or simply by a fraction, 15/3. The number that is being divided...

Draco, in astronomy

(Encyclopedia)Draco [Lat.,=the dragon], northern constellation lying SE of Ursa Minor and N of Lyra and Hercules. It is traditionally depicted as a dragon. Draco contains the bright star Eltanin (Gamma Draconis). T...

draft, in banking

(Encyclopedia)draft, in banking, order by one party to another party to pay a stated sum to the person or firm in whose favor the draft is made. It is similar in form to the ordinary bank check. Often the drawer an...

drainage, in agriculture

(Encyclopedia)drainage, in agriculture, the removal of excess water from the soil, either by a system of surface ditches, or by underground conduits if required by soil conditions and land contour. Diesel or centri...

drainage, in mining

(Encyclopedia)drainage, in mining, removal of water seeping into shafts and other underground mine workings from the surrounding ground. Unless seeping water is removed continually, it may endanger haulage and mini...

drum, in music

(Encyclopedia)CE5 Drums drum, in music, percussion instrument, known in various forms and played throughout the world and throughout history. Essentially a drum is a frame over which one or more membranes or sk...

Browse by Subject