Abscissa and ordinate

[citation needed] Though the word "abscissa" (from Latin linea abscissa 'a line cut off') has been used at least since De Practica Geometrie (1220) by Fibonacci (Leonardo of Pisa), its use in its modern sense may be due to Venetian mathematician Stefano degli Angeli in his work Miscellaneum Hyperbolicum, et Parabolicum (1659).

[4] In his 1892 work Vorlesungen über die Geschichte der Mathematik ("Lectures on history of mathematics"), volume 2, German historian of mathematics Moritz Cantor writes: Gleichwohl ist durch [Stefano degli Angeli] vermuthlich ein Wort in den mathematischen Sprachschatz eingeführt worden, welches gerade in der analytischen Geometrie sich als zukunftsreich bewährt hat.

Vielleicht kommt das Wort in Uebersetzungen der Apollonischen Kegelschnitte vor, wo Buch I Satz 20 von ἀποτεμνομέναις die Rede ist, wofür es kaum ein entsprechenderes lateinisches Wort als abscissa geben möchte.

[5] At the same time it was presumably by [Stefano degli Angeli] that a word was introduced into the mathematical vocabulary for which especially in analytic geometry the future proved to have much in store.

The use of the word ordinate is related to the Latin phrase linea ordinata appliicata 'line applied parallel'.

Cartesian plane with marked points (signed ordered pairs of coordinates). For any point, the abscissa is the first value (x coordinate), and the ordinate is the second value (y coordinate).