abscissa
Concise Oxford English Dictionary © 2008 Oxford University Press:
abscissa /abˈsɪsə/
▶noun (pl. abscissae /-siː/ or abscissas) Mathematics the distance from a point on a graph to the vertical or y-axis; the x-coordinate. Compare with ordinate.
– origin C17: from mod. L. abscissa (linea) ‘cut-off (line)’, fem. past part. of abscindere (see abscission).
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