binormal: Meaning and Definition of

bi•nor•mal

Pronunciation: (bī'nôr"mul, bī-nôr'-), [key]
— n. Geom.
  1. the normal to a curve, lying perpendicular to the osculating plane at a given point on the curve.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.