The Glossary module scans content for terms that are defined by site contributors. If Glossary locates a matching word within a page, the Glossary module will indicate that the term is contained in the site's glossary.
Term Indicator Example
Hovering briefly over the indicator with a mouse will cause a tool tip containing the term's definition to display. Clicking the indicator leads the user to that term presented within the whole glossary or directly to the detailed description of the term, if available.
Term Inside of Glossary
Glossary relies on the Taxonomy module. At least one vocabulary must be created within Taxonomy for Glossary to work. Glossary can work with multiple vocabularies, if available.
As a side note, care should be taken when developing Glossary terms. Depending on how your administrator configures Glossary on your site, as well as how terms are entered, Glossary may yield some unintended results. One common unintended result is when a word or acronym has a synonym that triggers Glossary. For example, if the acronym WHO (World Health Organization) were listed as a glossary term, Glossary may also indicate the term for the pronoun "who".