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wind tunnel

(Encyclopedia)wind tunnel, apparatus for studying the interaction between a solid body and an airstream. A wind tunnel simulates the conditions of an aircraft in flight by causing a high-speed stream of air to flow...

3D printer

(Encyclopedia)3D printer, computerized device that produces a three-dimensional object by creating it as a series of thin layers. The object is created from a model stored in computer-aided design file; the model i...

alimony

(Encyclopedia)alimony, in law, allowance for support that an individual pays to his or her former spouse, usually as part of a divorce settlement. It is based on the common law right of a wife to be supported by he...

executive order

(Encyclopedia)executive order, in the United States, official document initiated and signed by the president containing directives concerning how the executive branch shall carry out its responsibilities under the ...

dialysis

(Encyclopedia)dialysis dīălˈĭsĭs [key], in chemistry, transfer of solute (dissolved solids) across a semipermeable membrane. Strictly speaking, dialysis refers only to the transfer of the solute; transfer of t...

Cartesian coordinates

(Encyclopedia)CE5 Cartesian coordinates Cartesian coordinates kärtēˈzhən [key] [for René Descartes], system for representing the relative positions of points in a plane or in space. In a plane, the point P...

number

(Encyclopedia)number, entity describing the magnitude or position of a mathematical object or extensions of these concepts. A real or complex number z is called algebraic if it is the root of a polynomial equati...

tissue culture

(Encyclopedia)tissue culture, the propagation of plants through the placement of small amounts of undifferentiated tissue or single cells in an artificial environment. The tissue is placed in a nutrient medium that...

cyst

(Encyclopedia)cyst, abnormal sac in the body, filled with a fluid or semisolid and enclosed in a membrane. Cysts can be congenital but are usually acquired, the most common locations being the skin and the ovaries....

United States Merchant Marine Academy

(Encyclopedia)United States Merchant Marine Academy, at Kings Point, N.Y.; for the training of merchant marine officers; established 1936, opened 1943. The academy became coeducational in 1974. Candidates must be b...