Meaning of Cassegrain telescope

Cas'se•grain tel'escope

Pronunciation: (kas'u-grān"), [key]
— Astron. Astron.
  1. a reflecting telescope in which the light, passing through a central opening in the primary mirror, is brought into focus a short distance behind it by a secondary mirror. Also called
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.