gravitational lens: Meaning and Definition of

gravita'tional lens'

Pronunciation: [key]
— Astron. Astron.
  1. a heavy, dense body, as a galaxy, that lies along our line of sight to a more distant object, as a quasar, and whose gravitational field refracts the light of that object, splitting it into multiple images as seen from the earth.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.