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neostigmine

(Encyclopedia)neostigmine nēˌōstĭgˈmēn, –mĭn [key], drug used to mimic the effects of stimulation of the parasympathetic nervous system. Along with several other drugs that have a similar mode of action, i...

van der Waals, Johannes Diderik

(Encyclopedia)van der Waals, Johannes Diderik yōhäˈnəs dēˈdərĭk vän dər väls [key], 1837–1923, Dutch physicist. It had been known for some time that the behavior of real gases differs from that of an i...

Szymborska, Wisława

(Encyclopedia)Szymborska, Wisława wēswäˈvä shĭmbôrˈskä [key], 1923–2012, Polish poet, b. Bnin, studied Jagiellonian Univ., Kraków (1945–48). Although highly acclaimed in her homeland, Szymborska was l...

cacao

(Encyclopedia)cacao kəkäˈō, –kāˈ– [key], tropical tree (Theobroma cacao) of the family Sterculiaceae (sterculia family), native to South America, where it was first domesticated and was highly prized by t...

air mass

(Encyclopedia)air mass, large body of air within the earth's atmosphere in which temperature and humidity, although varying at different heights, remain similar throughout the body at any one height. Air masses for...

ammonia

(Encyclopedia)ammonia, chemical compound, NH3, colorless gas that is about one half as dense as air at ordinary temperatures and pressures. It has a characteristic pungent, penetrating odor. Ammonia forms a minute ...

adaptation

(Encyclopedia)adaptation, in biology, has several meanings. It can mean the adjustment of living matter to environmental conditions and to other living things either in an organism's lifetime (physiological adaptat...

hydrogen

(Encyclopedia)hydrogen hīˈdrəjən [key] [Gr.,=water forming], gaseous chemical element; symbol H; at. no. 1; interval in which at. wt. ranges 1.00784–1.00811; m.p. −259.14℃; b.p. −252.87℃; density 0.08...

Little Entente

(Encyclopedia)Little Entente äntäntˈ [key], loose alliance formed in 1920–21 by Czechoslovakia, Romania, and Yugoslavia. Its specific purposes were the containment of Hungarian revisionism (of the terms of the...

hardness

(Encyclopedia)hardness, property of matter commonly described as the resistance of a substance to being scratched by another substance. The degree of hardness is relative, different substances being compared with o...