aristotle - 2:15 pm on Jul 19, 2010 (gmt 0)
Apparently it isn't essential to use the html definition tags. Asher02 said that his glossaries don't use them, yet Google still includes his definitions in the results for define: searches. I did a few searches as a test and found some other examples of this as well.
So If for some reason you can't use the html tags, you can try using a list format with bolded terms, and giving the page the title "Glossary". There's a chance that this would work.