Columbia Encyclopedia

Search results

500 results found

coast

(Encyclopedia)coast, land bordering an ocean or other large body of water. The line of contact between the land and water surfaces is called the shoreline. It fluctuates with the waves and tides. Sometimes the term...

antifreeze

(Encyclopedia)antifreeze, substance added to a solvent to lower its freezing point. The solution formed is called an antifreeze mixture. Antifreeze is typically added to water in the cooling system of an internal-c...

leptospirosis

(Encyclopedia)leptospirosis lĕpˌtəspīrōˈsĭs [key], febrile disease caused by bacteria of the genus Leptospirae. The disease may affect dogs, cattle, pigs, sheep, goats, and horses and is also transmissible t...

pH

(Encyclopedia)pH, range of numbers expressing the relative acidity or alkalinity of a solution. In general, pH values range from 0 to 14. The pH of a neutral solution, i.e., one which is neither acidic nor alkaline...

phospholipid

(Encyclopedia)phospholipid fŏsˌfōlĭpˈĭd [key], lipid that in its simplest form is composed of glycerol bonded to two fatty acids and a phosphate group. The resulting compound called phosphatidic acid contains...

dam

(Encyclopedia)dam, barrier, commonly across a watercourse, to hold back water, often forming a reservoir or lake; dams are also sometimes used to control or contain rockslides, mudflows, and the like in regions whe...

Frasch process

(Encyclopedia)Frasch process fräsh [key] [for Herman Frasch, the German-American chemist who devised it], process for the extraction of sulfur from subsurface deposits. Three pipes, one inside another, are sunk to...

flat-coated retriever

(Encyclopedia)flat-coated retriever, breed of large sporting dog developed in England in the mid-19th cent. It stands about 23 in. (58 cm) high at the shoulder and weighs about 65 lb (30 kg). Its dense, flat coat o...

mother-of-pearl

(Encyclopedia)mother-of-pearl or nacre nāˈkər [key], the iridescent substance that forms the lining of the shells of some fresh-water and some salt-water mollusks. Like the pearl it is a secretion of the mantle,...

oasis

(Encyclopedia)oasis ōāˈsĭs [key], an area within a desert where the water table reaches the surface, with enough moisture to permit the growth of vegetation. The water may come up to the surface in springs, or ...