A glossary is a sort of miniature dictionary appended to a book, article or academic paper. The glossary provides the reader with definitions of unfamiliar terms used in the main text, allowing them to fully comprehend what you are writing without having to include "Lemony-Snicketesque" explanations in the middle of your writing. Following the format used by most books to write your glossary entries will help the reader easily understand how to use it and find the information he needs.
Type the term to be defined in bold text. This will help the reader searching through the entries to find the correct word. A glossary term is usually uncapitalized, unless it happens to be a proper name.
Provide a definition for your term. Express this in a single sentence, if possible, and use only words with which your readership will already be familiar. If you can't define the term without using another obscure term, include the secondary term in your glossary as well.
Direct the reader to other related glossary entries, if necessary. Do this if your entry includes unfamiliar terms in the definition or is very similar to a different term found elsewhere in your glossary. If the two terms are synonyms, only provide the full definition under the first of them, putting "See [other term]" as the entry for the second.