ABSCISSA

abscissa

(noun) the value of a coordinate on the horizontal axis

Source: WordNet® 3.1

Etymology

Noun

abscissa (plural abscissas or abscissae or abscissæ)

(geometry) The first of the two terms by which a point is referred to, in a system of fixed rectilinear coordinate (Cartesian coordinate) axes.[First attested in the late 17^th century.]

The point $$(3,2)$$ has 3 as its abscissa and 2 as its ordinate.

(geometry) The horizontal line representing an axis of a Cartesian coordinate system, on which the abscissa (sense above) is shown.

Usage notes

Originally, it referred to the portion of a line between a fixed point on that line and the intersection of that line with an ordinate.

Synonyms

• absciss

Hypernyms

• (first of two coordinates): coordinate

• (horizontal line): axis

Coordinate terms

• ordinate

Source: Wiktionary

Ab*scis"sa, n.; E. pl. Abscissas, L. pl. Abscissæ. Etym: [L., fem. of abscissus, p. p. of absindere to cut of. See Abscind.] (Geom.)

Definition: One of the elements of reference by which a point, as of a curve, is referred to a system of fixed rectilineal coördinate axes.

Note: 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.

Source: Webster’s Unabridged Dictionary 1913 Edition