Cite any glossary with the author and the copyright date in parentheses for the in-text citation. For example: (Underhill, 1987).
Cite a core glossary with the name of the editor, the copyright date, the title and volume number if applicable, the publisher and the location of the publishing house. The glossary title should be in italics. For example: Underhill, T. (Ed.). (1987). Glossary of terms (Vols. 2-6). Seattle, WA: Reference Publishers.
Cite an edited book's glossary with the author, the publication year, the chapter title which is "glossary" in this case, the editor(s) names, the book title, the page numbers referenced and the publisher information. For example: Samuels, C. (2008). Glossary. In T. Underhill (Ed.), Citation styles and formats (278-284). Boise, ID: Citation Publishers.
Cite a glossary from a book without an editor in the same manner as a regular book. You can note in the body of the paper that you are referencing the glossary. You need the author, title and relevant publication information. For example: Samuels, C. (1996). Advertising in the sixties. New York, NY: Mad Men Publishers.