# Projection of a point on a plane

Projection of a point on a plane
Projection Pro*jec"tion, n. [L. projectio: cf. F. projection.] [1913 Webster] 1. The act of throwing or shooting forward. [1913 Webster]

2. A jutting out; also, a part jutting out, as of a building; an extension beyond something else. [1913 Webster]

3. The act of scheming or planning; also, that which is planned; contrivance; design; plan. --Davenant. [1913 Webster]

4. (Persp.) The representation of something; delineation; plan; especially, the representation of any object on a perspective plane, or such a delineation as would result were the chief points of the object thrown forward upon the plane, each in the direction of a line drawn through it from a given point of sight, or central point; as, the projection of a sphere. The several kinds of projection differ according to the assumed point of sight and plane of projection in each. [1913 Webster]

5. (Geog.) Any method of representing the surface of the earth upon a plane. [1913 Webster]

{Conical projection}, a mode of representing the sphere, the spherical surface being projected upon the surface of a cone tangent to the sphere, the point of sight being at the center of the sphere.

{Cylindric projection}, a mode of representing the sphere, the spherical surface being projected upon the surface of a cylinder touching the sphere, the point of sight being at the center of the sphere.

{Globular}, {Gnomonic}, {Orthographic}, {projection},etc. See under {Globular}, {Gnomonic}, etc.

{Mercator's projection}, a mode of representing the sphere in which the meridians are drawn parallel to each other, and the parallels of latitude are straight lines whose distance from each other increases with their distance from the equator, so that at all places the degrees of latitude and longitude have to each other the same ratio as on the sphere itself.

{Oblique projection}, a projection made by parallel lines drawn from every point of a figure and meeting the plane of projection obliquely.

{Polar projection}, a projection of the sphere in which the point of sight is at the center, and the plane of projection passes through one of the polar circles.

{Powder of projection} (Alchemy.), a certain powder cast into a crucible or other vessel containing prepared metal or other matter which is to be thereby transmuted into gold.

{Projection of a point on a plane} (Descriptive Geom.), the foot of a perpendicular to the plane drawn through the point.

{Projection of a straight line of a plane}, the straight line of the plane connecting the feet of the perpendiculars let fall from the extremities of the given line. [1913 Webster]

Syn: See {Protuberance}. [1913 Webster] [1913 Webster]

The Collaborative International Dictionary of English. 2000.

### Look at other dictionaries:

• Projection of a straight line of a plane — Projection Pro*jec tion, n. [L. projectio: cf. F. projection.] [1913 Webster] 1. The act of throwing or shooting forward. [1913 Webster] 2. A jutting out; also, a part jutting out, as of a building; an extension beyond something else. [1913… …   The Collaborative International Dictionary of English

• Projection — Pro*jec tion, n. [L. projectio: cf. F. projection.] [1913 Webster] 1. The act of throwing or shooting forward. [1913 Webster] 2. A jutting out; also, a part jutting out, as of a building; an extension beyond something else. [1913 Webster] 3. The… …   The Collaborative International Dictionary of English

• projection — Pro*jec tion, n. [L. projectio: cf. F. projection.] [1913 Webster] 1. The act of throwing or shooting forward. [1913 Webster] 2. A jutting out; also, a part jutting out, as of a building; an extension beyond something else. [1913 Webster] 3. The… …   The Collaborative International Dictionary of English

• Projection (mathematics) — Commutativity of this diagram is the universality of projection π, for any map f and set X. Generally speaking, in mathematics, a projection is a mapping of a set (or of a mathematical structure) which is idempotent, which means that a projection …   Wikipedia

• Point on plane closest to origin — In Euclidean 3 space we will find the point on an arbitrary plane that is closest to the origin using the method of Lagrange multipliers. First, let us start with an arbitrary plane, ax + by + cz = d. The distance, L, from the origin to a point… …   Wikipedia

• projection — [ prɔʒɛksjɔ̃ ] n. f. • 1314; lat. projectio, de projectus, p. p. de projicere 1 ♦ Action de jeter, de lancer en avant (⇒ 1. jet; projeter, I ). Projection de liquide, de vapeur. Lancement, jet (de projectiles). Projection de pierres, d obus.… …   Encyclopédie Universelle

• Projection conforme — Projection cartographique Le choix d une projection et la conversion d une projection à une autre comptent parmi les difficultés que les cartographes ont dû affronter. L informatique leur a beaucoup apporté de ce point de vue La projection… …   Wikipédia en Français

• Projection en relief stereoscopique — Projection en relief stéréoscopique Cet article fait partie de la série Photographie …   Wikipédia en Français

• Conical projection — Projection Pro*jec tion, n. [L. projectio: cf. F. projection.] [1913 Webster] 1. The act of throwing or shooting forward. [1913 Webster] 2. A jutting out; also, a part jutting out, as of a building; an extension beyond something else. [1913… …   The Collaborative International Dictionary of English

• Cylindric projection — Projection Pro*jec tion, n. [L. projectio: cf. F. projection.] [1913 Webster] 1. The act of throwing or shooting forward. [1913 Webster] 2. A jutting out; also, a part jutting out, as of a building; an extension beyond something else. [1913… …   The Collaborative International Dictionary of English