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dysentery

(Encyclopedia)dysentery dĭsˈəntĕrˌē [key], inflammation of the intestine characterized by the frequent passage of feces, usually with blood and mucus. The two most common causes of dysentery are infection wit...

Chomsky, Noam

(Encyclopedia)Chomsky, Noam nōm chŏmˈskē [key], 1928–, educator and linguist, b. Philadelphia. Chomsky, who has taught at the Massachusetts Institute of Technology since 1955, developed a theory of transforma...

free will

(Encyclopedia)free will, in philosophy, the doctrine that an individual, regardless of forces external to him, can and does choose at least some of his actions. The existence of free will is challenged by determini...

anesthesia

(Encyclopedia)anesthesia ănĭsthēˈzhə [key] [Gr.,=insensibility], loss of sensation, especially that of pain, induced by drugs, especially as a means of facilitating safe surgical procedures. Early modern medic...

skeleton, in anatomy

(Encyclopedia)CE5 Human skeleton skeleton, in anatomy, the stiff supportive framework of the body. The two basic types of skeleton found among animals are the exoskeleton and the endoskeleton. The shell of the ...

sickle cell disease

(Encyclopedia)sickle cell disease or sickle cell anemia, inherited disorder of the blood in which the oxygen-carrying hemoglobin pigment in erythrocytes (red blood cells) is abnormal. This “hemoglobin-S” crysta...

cocaine

(Encyclopedia)cocaine kōkānˈ, kōˈkān [key], alkaloid drug derived from the leaves of the coca shrub. A commonly abused illegal drug, cocaine has limited medical uses, most often in surgical applications that ...

Platyhelminthes

(Encyclopedia)CE5 A. Planaria, representative of the phylum Platyhelminthes B. Internal anatomy of Planaria Platyhelminthes plătˌēhĕlmĭnˈthēz [key], phylum containing about 20,000 species of soft-bodied,...

competition, in economics

(Encyclopedia)competition, in economics, rivalry in supplying or acquiring an economic service or good. Sellers compete with other sellers, and buyers with other buyers. In its perfect form, there is competition am...

Scott, Sir Walter

(Encyclopedia)Scott, Sir Walter, 1771–1832, Scottish novelist and poet, b. Edinburgh. He is considered the father of both the regional and the historical novel. Scott's narrative poems introduced a form of v...