Normal equations
Normal Nor"mal (n[^o]r"mal), a. [L. normalis, fr. norma rule, pattern, carpenter's square; prob. akin to noscere to know; cf. Gr. gnw`rimos well known, gnw`mwn gnomon, also, carpenter's square: cf. F. normal. See {Known}, and cf. {Abnormal}, {Enormous}.] [1913 Webster] 1. According to an established norm, rule, or principle; conformed to a type, standard, or regular form; performing the proper functions; not abnormal; regular; natural; analogical. [1913 Webster]

Deviations from the normal type. --Hallam. [1913 Webster]

2. (Geom.) According to a square or rule; perpendicular; forming a right angle; as, a line normal to the base. Specifically: Of or pertaining to a normal. [1913 Webster]

3. (Chem.) Standard; original; exact; typical. Specifically: (a) (Quantitative Analysis) Denoting a solution of such strength that every cubic centimeter contains the same number of milligrams of the element in question as the number of its molecular weight. (b) (Chem.) Denoting certain hypothetical compounds, as acids from which the real acids are obtained by dehydration; thus, normal sulphuric acid and normal nitric acid are respectively {S(OH)6}, and {N(OH)5}. (c) (Organ. Chem.) Denoting that series of hydrocarbons in which no carbon atom is bound to more than two other carbon atoms; as, normal pentane, hexane, etc. Cf. {Iso-}. [1913 Webster]

{Normal equations} (Method of Least Squares), a set of equations of the first degree equal in number to the number of unknown quantities, and derived from the observations by a specified process. The solution of the normal equations gives the most probable values of the unknown quantities.

{Normal group} (Geol.), a group of rocks taken as a standard. --Lyell.

{Normal place} (of a planet or comet) (Astron.), the apparent place in the heavens of a planet or comet at a specified time, the place having been determined by a considerable number of observations, extending perhaps over many days, and so combined that the accidental errors of observation have largely balanced each other.

{Normal school}, a school whose methods of instruction are to serve as a model for imitation; an institution for the training of teachers. [1913 Webster]

Syn: {Normal}, {Regular}, {Ordinary}.

Usage: Regular and ordinary are popular terms of well-known signification; normal has now a more specific sense, arising out of its use in science. A thing is normal, or in its normal state, when strictly conformed to those principles of its constitution which mark its species or to the standard of a healthy and natural condition. It is {abnormal} when it departs from those principles. [1913 Webster]

The Collaborative International Dictionary of English. 2000.

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• Normal — Nor mal (n[^o]r mal), a. [L. normalis, fr. norma rule, pattern, carpenter s square; prob. akin to noscere to know; cf. Gr. gnw rimos well known, gnw mwn gnomon, also, carpenter s square: cf. F. normal. See {Known}, and cf. {Abnormal},… …   The Collaborative International Dictionary of English

• Normal group — Normal Nor mal (n[^o]r mal), a. [L. normalis, fr. norma rule, pattern, carpenter s square; prob. akin to noscere to know; cf. Gr. gnw rimos well known, gnw mwn gnomon, also, carpenter s square: cf. F. normal. See {Known}, and cf. {Abnormal},… …   The Collaborative International Dictionary of English

• Normal place — Normal Nor mal (n[^o]r mal), a. [L. normalis, fr. norma rule, pattern, carpenter s square; prob. akin to noscere to know; cf. Gr. gnw rimos well known, gnw mwn gnomon, also, carpenter s square: cf. F. normal. See {Known}, and cf. {Abnormal},… …   The Collaborative International Dictionary of English

• Normal school — Normal Nor mal (n[^o]r mal), a. [L. normalis, fr. norma rule, pattern, carpenter s square; prob. akin to noscere to know; cf. Gr. gnw rimos well known, gnw mwn gnomon, also, carpenter s square: cf. F. normal. See {Known}, and cf. {Abnormal},… …   The Collaborative International Dictionary of English

• Normal (mathematics) — In mathematics, normal can have several meanings:* Surface normal, a vector (or line) that is perpendicular to a surface. * Normal component, the component of a vector that is perpendicular to a surface. ** Normal curvature, of a curve on a… …   Wikipedia

• Equations de Gauss-Codazzii — Équations de Gauss Codazzii En géométrie riemannienne, les équations de Gauss Codazzi Mainardi sont des équations fondamentales dans le cadre de la théorie des hypersurfaces plongées dans un espace euclidien, et plus généralement des sous… …   Wikipédia en Français

• Équations de Gauss-Codazzii — En géométrie riemannienne, les équations de Gauss Codazzi Mainardi sont des équations fondamentales dans le cadre de la théorie des hypersurfaces plongées dans un espace euclidien, et plus généralement des sous variétés d une variété riemannienne …   Wikipédia en Français

• Équations de gauss-codazzii — En géométrie riemannienne, les équations de Gauss Codazzi Mainardi sont des équations fondamentales dans le cadre de la théorie des hypersurfaces plongées dans un espace euclidien, et plus généralement des sous variétés d une variété riemannienne …   Wikipédia en Français

• Equations fondamentales de la mecanique des milieux continus — Équations fondamentales de la mécanique des milieux continus Les équations fondamentales de la mécanique des milieux continus regroupent les énoncés mathématiques les plus couramment utilisés dans le cadre de la mécanique des milieux continus,… …   Wikipédia en Français

• Équations fondamentales de la mécanique des milieux continus) — Équations fondamentales de la mécanique des milieux continus Les équations fondamentales de la mécanique des milieux continus regroupent les énoncés mathématiques les plus couramment utilisés dans le cadre de la mécanique des milieux continus,… …   Wikipédia en Français