subtangent

Century Dictionary and Cyclopedia

1. n. In analytical geometry, the part of the axis of abscissas of a curve cut off between the tangent and the ordinate.

Wiktionary

1. n. geometry The part of the axis contained between the ordinate and tangent drawn to the same point in a curve.

GNU Webster's 1913

1. n. (Geom.) The part of the axis contained between the ordinate and tangent drawn to the same point in a curve.