[ duhb-uh l-boo k ]
/ ˈdʌb əlˈbʊk /

verb (used with object)

to overbook by accepting more than one reservation for the same hotel room, airplane seat, etc.
to make reservations for (more than one hotel accommodation, seat on a plane, etc.) so as to be certain of obtaining at least one of them.

verb (used without object)

to make double reservations for passenger space, a hotel room, etc.

Origin of double-book

First recorded in 1965–70 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019