To overbook is to reserve seats or rooms for more people than there are seats or rooms available.(verb)
An example of overbook is to sell more tickets than there are seats on a flight.
See overbook in Webster's New World College Dictionary
transitive verb, intransitive verb
See overbook in American Heritage Dictionary 4
verb o·ver·booked, o·ver·book·ing, o·ver·books verb, transitive
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