1.NounThe first of the two terms by which a point is referred to, in a system of fixed rectilinear coordinate (Cartesian coordinate) axes. .mw-parser-output .defdate{font-size:smaller}
"The point
(
3
,
2
)
{\displaystyle (3,2)}
has 3 as its abscissa and 2 as its ordinate."
2.NounThe horizontal line representing an axis of a Cartesian coordinate system, on which the abscissa (sense above) is shown.