A glossary is an alphabetical list of terms or words used in a specific field, along with their definitions or explanations. Glossaries are commonly found in academic, technical, or professional works and provide a reference resource for the reader to understand the specific terminology used in that field.

They can also be used to define terms in different languages or to explain jargon or specialized terms that may not be widely understood. A glossary can be found at the end of a book, in an appendix, or as a standalone document and can be useful for clarifying the meaning of unfamiliar words or phrases.