Key

A key is a machine, usually lacking moving parts, made of a durable material and in a reasonably complex format to prevent duplication, used to gain access to secured areas or storage.

The word key when used in some contexts, particularly relating to demons and interworld travel, can refer to demonic keys, which are devices used for teleportation.

Twine Encyclopaedia has no key in the sense of a glossary or index, instead using dynamically generated page listings and hyperlinked references between pages.