The National Weather Service has added glossary links for technical terms and acronyms in the text products surfaced via their website, e.g. the Huntsville Area Forecast Discussion. The links point to a separate glossary application, which doesn't seem to succeed in looking up the word that's passed by the link.
This sort of functionality should be a standard component, IMO, of any technical document (a classics journal article, say) that's posted to the web with any desire to reach students or a non-specialist audience. With a bit of infrastructure work, and maintenance of a glossary, it could be made to happen almost automagically as part of a publishing workflow. I'm sure there are sites where that's already the case.