Meaning of overbook

o•ver•book

Pronunciation: (ō"vur-book'), [key]
— v.t.
  1. to accept reservations for in excess of the number that can be accommodated: The airline routinely overbooks its flights so as to fill its planes even if there are last-minute cancellations.
—v.i.
  1. to accept reservations in excess of the number that can be accommodated: If the hotel has overbooked, some of the conventioners won't have a place to stay.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.