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medicine

(Encyclopedia)medicine, the science and art of treating and preventing disease. Modern medicine, characterized by growing specialization and a complex diagnostic and therapeutic technology, faces problems in the...

Phoenicia

(Encyclopedia)Phoenicia fĭnēˈshə [key], ancient territory occupied by Phoenicians. The name Phoenicia also appears as Phenice and Phenicia. These people were Canaanites (see Canaan), and in the 9th cent. b.c. t...

rain

(Encyclopedia)rain, precipitation in liquid form. It consists of drops of water falling from clouds; if the drops are very small, they are collectively termed drizzle. Rain plays a key role in the hydrologic, or wa...

drone

(Encyclopedia)drone or remotely piloted vehicle, a pilotless craft guided by remote control. Aircraft, ships, and land vehicles can be designed or outfitted as drones. Underwater vessels—both piloted and pilotles...

cigar and cigarette

(Encyclopedia)cigar and cigarette, tubular rolls of tobacco designed for smoking. Cigars consist of filler leaves held together by binder leaves and covered with a wrapper leaf, which is rolled spirally around the ...

genetic engineering

(Encyclopedia)CE5 Genetic engineering: Gene-splicing techniques genetic engineering, the use of various methods to manipulate the DNA (genetic material) of cells to change hereditary traits or produce biologica...

food preservation

(Encyclopedia)food preservation, methods of preparing food so that it can be stored for future use. Because most foods remain edible for only a brief period of time, people since the earliest ages have experimented...

poliomyelitis

(Encyclopedia)poliomyelitis pōˌlēōmīˌəlīˈtĭs [key], polio, or infantile paralysis, acute viral infection, mainly of children but also affecting older persons. Historically, there were three immunologic ty...

cactus

(Encyclopedia)cactus, any plant of the family Cactaceae, a large group of succulents found almost entirely in the New World. A cactus plant is conspicuous for its fleshy green stem, which performs the functions of ...

social work

(Encyclopedia)social work, organized effort to help individuals and families to adjust themselves to the community, as well as to adapt the community to the needs of such persons and families. Social work emerge...