overbook
verb /ˌəʊvəˈbʊk/
  /ˌəʊvərˈbʊk/
 [transitive, intransitive]Verb Forms
| present simple I / you / we / they overbook |  /ˌəʊvəˈbʊk/  /ˌəʊvərˈbʊk/ | 
| he / she / it overbooks |  /ˌəʊvəˈbʊks/  /ˌəʊvərˈbʊks/ | 
| past simple overbooked |  /ˌəʊvəˈbʊkt/  /ˌəʊvərˈbʊkt/ | 
| past participle overbooked |  /ˌəʊvəˈbʊkt/  /ˌəʊvərˈbʊkt/ | 
| -ing form overbooking |  /ˌəʊvəˈbʊkɪŋ/  /ˌəʊvərˈbʊkɪŋ/ | 
- overbook (something) to sell more tickets on a plane or reserve more rooms in a hotel than there are places available- The flight was heavily overbooked.