Answer:
glossary
Step-by-step explanation:
because glossary means an alphabetical list of words relating to a specific subject, text, or dialect, with explanations; a brief dictionary.
and Dictionary means a book or electronic resource that lists the words of a language (typically in alphabetical order) and gives their meaning, or gives the equivalent words in a different language, often also providing information about pronunciation, origin, and usage.
and encyclopedia means a book or set of books giving information on many subjects or on many aspects of one subject and typically arranged alphabetically.
and thesaurus means a book that lists words in groups of synonyms and related concepts.
