noun which may take the genitive case particle 'no'
unregistered; non-registered
Describes something not yet entered into an official list, database, or registry. Often used in administrative, legal, or technical contexts.
Unregistered users cannot use this feature.
That vehicle is still unregistered.
登録済み describes something that has already been registered, while 未登録 describes something that has not yet been registered.
Compound of 未 (mi, 'not yet') + 登録 (tōroku, 'registration').