# abscissa

## Definitions

• WordNet 3.6
• n abscissa the value of a coordinate on the horizontal axis
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Webster's Revised Unabridged Dictionary
• n Abscissa (Geom) One of the elements of reference by which a point, as of a curve, is referred to a system of fixed rectilineal coördinate axes.When referred to two intersecting axes, one of them called the axis of abscissas, or of X, and the other the axis of ordinates, or of Y, the abscissa of the point is the distance cut off from the axis of X by a line drawn through it and parallel to the axis of Y. When a point in space is referred to three axes having a common intersection, the abscissa may be the distance measured parallel to either of them, from the point to the plane of the other two axes. Abscissas and ordinates taken together are called coördinates. -- OX or PY is the abscissa of the point P of the curve, OY or PX its ordinate, the intersecting lines OX and OY being the axes of abscissas and ordinates respectively, and the point O their origin.
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Century Dictionary and Cyclopedia
• n abscissa In mathematics: In the conic sections, that part of a transverse axis which lies between its vertex and a perpendicular ordinate to it from a given point of the conic. Thus (fig. 1), in the parabola PAC, AM, the part of the axis AB cut off by the ordinate PM, is the abscissa of the point P. In the system of Cartesian coördinates, a certain line used in determining the position of a point in a plane. Thus (fig. 2), let two fixed intersecting lines (axes) OY and OX be taken, and certain directions on them (as from O toward X and from O toward Y) be assumed as positive. From any point, as P, let a line be drawn parallel to OY and cutting OX in M. Then will the two quantities OM and MP, with the proper algebraic sign, determine the position of the point P. OM, or its value, is called the abscissa of the point, and the fixed line X'X is called the axis of abscissas. See coördinate, n., 2.
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Chambers's Twentieth Century Dictionary
• n Abscissa the straight line cut off or intercepted between the vertex of a curve and an ordinate, measured along the principal axis
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## Etymology

Webster's Revised Unabridged Dictionary
L., fem. of abscissus, p. p. of absindere, to cut of. See Abscind
Chambers's Twentieth Century Dictionary
L. abscissus, cut off, pa.p. of abscindĕreab, from, scindĕre, to cut.

## Usage

### In literature:

For the lines of beauty there are no abscissae and ordinates; circles and ellipses are not described by means of their algebraical formulae.
"On War" by Carl von Clausewitz
He does not see the combinations of the abscissas and ordinates very clearly.
"The Life of the Fly" by J. Henri Fabre
To provide for such cases the curve is drawn as if it never touched the abscissa.
The measured lengths are marked off on ordinates erected on an abscissa, along which the times are noted.
"Encyclopaedia Britannica, 11th Edition, Volume 3, Part 1, Slice 2" by Various
The abscissa of such a curve is the reading of the instrument to be corrected.
"Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 1" by Various
The abscissa of the F.P.
"Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 3" by Various
Curves have been prepared having pressure as an abscissa and elasticity as ordinate.
"Paint Technology and Tests" by Henry A. Gardner
The abscissa and the ordinate do not measure commensurable units.
"The Place of Science in Modern Civilisation and Other Essays" by Thorstein Veblen
Let a, b be the abscissae of these points.
"Encyclopaedia Britannica, 11th Edition, Volume 14, Slice 5" by Various
Abscissa represents duration of application of stimulus.
"Life Movements in Plants, Volume II, 1919" by Sir Jagadis Chunder Bose
B abscissae extension in eighths of an inch, ordinates weights in ounces.
"The Theory and Practice of Model Aeroplaning" by V. E. Johnson
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### In science:

The turning radii Rm can be found as an abscissa of intersection points of a curve M = M(R) and of a direct M = M .
The quasi-classical model of the spherical configuration in general relativity
There is a vertical jump from 104 to 106 in an extremely small interval of the abscissa.
The linear MHD Taylor-Couette instability for liquid sodium
The impurity levels Ea = ±1.25∆ are indicated by dots on the abscissa.
Carrier States and Ferromagnetism in Diluted Magnetic Semiconductors
The impurity levels Ea = ±1.25∆ are indicated by dots on the abscissa.
Carrier States and Ferromagnetism in Diluted Magnetic Semiconductors
The impurity level Ea = −1.25∆ is indicated by the dot on the abscissa.
Carrier States and Ferromagnetism in Diluted Magnetic Semiconductors
The impurity level Ea = −1.25∆ is indicated by a dot on the abscissa.
Carrier States and Ferromagnetism in Diluted Magnetic Semiconductors
Trivial approximation is to put together points by abscissas.
Functional Equation of the Rate of Inflation
In these illustrations, the values n are chosen as abscissas.
Ornstein-Zernike equation and Percus-Yevick theory for molecular crystals
The abscissa is vrot /v∞ relevant for the models presented in this paper.
The Hanle Effect as a Diagnostic of Magnetic Fields in Stellar Envelopes IV. Application to Polarized P Cygni Wind Lines
The straight line in Figure 1 is the expected number of chance coincidences between AGN and FIRST sources, in annuli of radius shown on the abscissa and width 5 arcsec around the AGN.
Radio Emission from AGN detected by the VLA FIRST Survey
This is easy to write down and work with, and has some motivation, as it describes the expansion/contraction of the abscissa variable at a constant rate.
Asymmetric Statistical Errors
Therefore, if f exhibits a collinear triple, it must have some point with abscissa 0.
Collinear Points in Permutations
We choose the point O as an origin, then direct the abscissa axis along the ray OX and get the ordinate axis from the abscissa axis rotating it by 90◦ .
Course of differential geometry
The abscissa denotes effective wave number νy , and the ordinate does square of the growth rate.
Parker Instability in a Self-Gravitating Magnetized Gas Disk: I. Linear Stability Analysis
The abscissa denotes effective wave number νy , and the ordinate does square of the growth rate.
Parker Instability in a Self-Gravitating Magnetized Gas Disk: I. Linear Stability Analysis
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