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riot, rout, and unlawful assembly

(Encyclopedia)riot, rout, and unlawful assembly, in law, varying degrees of concerted disturbance of the peace. At common law, an unlawful assembly is a gathering of at least three persons whose conduct causes obse...

seeing

(Encyclopedia)seeing, in astronomy, the clarity with which stars and other celestial objects can be observed. It is primarily determined by the atmosphere of the earth. The most obvious phenomenon is twinkling, whe...

common-ion effect

(Encyclopedia)common-ion effect, decrease in solubility of an ionic salt, i.e., one that dissociates in solution into its ions, caused by the presence in solution of another solute that contains one of the same ion...

convection

(Encyclopedia)convection, mode of heat transfer in fluids (liquids and gases). Convection depends on the fact that, in general, fluids expand when heated and thus undergo a decrease in density (since a given volume...

glaucoma

(Encyclopedia)glaucoma glôkōˈmə [key], ocular disorder characterized by pressure within the eyeball caused by an excessive amount of aqueous humor (the fluid substance filling the eyeball). This causes pressure...

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...

hostage

(Encyclopedia)hostage, person held by another as a guarantee that certain actions or promises will or will not be carried out. During periods of internal turmoil, insurgents often seize hostages; recent examples in...

Jehovah's Witnesses

(Encyclopedia)Jehovah's Witnesses, Christian group originating in the United States at the end of the 19th cent., organized by Charles Taze Russell, whose doctrine centers on the Second Coming of Christ. The Witnes...

guardian and ward

(Encyclopedia)guardian and ward, in law. A guardian is someone who by appointment or by relationship has the care of a person or that person's property, or both. The protected individual, known as the ward, is cons...

placebo

(Encyclopedia)placebo pləsēˈbō [key], inert substance given instead of a potent drug. Placebo medications are sometimes prescribed when a drug is not really needed or when one would not be appropriate because t...