What is authorisation (Autorisierung)?

Authorisation is the timely process of granting or denying the use of a resource to an authenticated subject on the basis of previously defined rules.

Two words in that sentence carry the meaning: authenticated (authorisation presupposes authentication) and previously defined (the rules come from definition time, the decision happens at runtime). Synonyms: Berechtigung in the sense of the act, authorization.

Go deeper:

• Authorization (Wikipedia) — specifying access rights and how that differs from verifying identity.