subtangent: Meaning and Definition of

sub•tan•gent

Pronunciation: (sub-tan'junt), [key]
— n. Geom.
  1. the part of the x-axis cut off between the ordinate of a given point of a curve and the tangent at that point.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.