accretion disk: Meaning and Definition of

accre'tion disk"

Pronunciation: [key]
— Astron. Astron.
  1. the rapidly spinning disk of gas that forms around the more compact component of a close binary star system as mass is transferred to the compact companion from the primary star.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.