booker

n. one who orders in advance, one who is registered

Booker may refer to a number of different locations, occupations, events, people and other things.
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Noun
1. someone who engages a person or company for performances
(synonym) booking agent
(hypernym) agent
(hyponym) showman, promoter, impresario
(derivation) book

(n.)
One who enters accounts or names, etc., in a book; a bookkeeper.
  

      brooke