0 past simple and past participle of book
1 to arrange to have a seat, room, performer, etc. at a particular time in the future:
[ + two objects ] I've booked us two tickets to see "Carmen"/I've booked two tickets for us to see "Carmen".
She'd booked a table for four at their favourite restaurant.
The hotel/restaurant/theatre is fully booked (up) (= all the rooms/tables/tickets have been taken).
I'd like to go but I'm booked up (= I have arranged to do other things) until the weekend.
2 If a police officer, referee, etc. books someone, they write down the person's name in an official record because they have done something wrong:
I've booked a table at the restaurant for nine o'clock.
In the clinic, the administrator who had booked the play was clearly impressed and wanted to talk further about it.
Mailinglist subscribers and regular patrons booked many of the seats, limiting the size of a new and younger audience.
She booked at 11 weeks gestation when no problems were found.