Meaning of inflationary universe

infla'tionary u'niverse

Pronunciation: [key]
— Astron. Astron.
  1. a version of the big bang theory in which the universe underwent very rapid growth during the first fraction of a second before it settled down to its current rate of expansion.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.