registration number
noun /ˌredʒɪˈstreɪʃn nʌmbə(r)/
/ˌredʒɪˈstreɪʃn nʌmbər/
(also registration)
(both British English) (North American English license (plate) number)
- the series of letters and numbers that are shown on a number plate at the front and back of a vehicle to identify it
- I gave the registration number of the car to the police.
Oxford Collocations DictionaryRegistration number is used after these nouns:- vehicle