Lagrangian point: Meaning and Definition of

Lagrang'ian point"

Pronunciation: [key]
— Astron. Astron.
  1. one of five points in the orbital plane of two bodies orbiting about their common center of gravity at which another body of small mass can be in equilibrium.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.