Definition of unpostponable in English:

unpostponable

Pronunciation /(ˌ)ʌnpəˈspəʊnəbl/ /(ˌ)ʌnˌpəʊs(t)ˈpəʊnəbl/

adjective

  • That cannot be postponed.

Origin

Early 19th century; earliest use found in True Briton. From un- + postponable.