Wiki good for 'glossary of terms'?

Hello everyone,

We are looking to build a ‘glossary of terms’ (sort of a technical dictionary) for our website. Our website is in Joomla, but there are no good extensions for what we are looking for. Plus, we want the glossary to be on a separate (sub)domain, but linkable (the terms) from the main site.

We only want to allow selected administrator to add and edit the contents. We want a solution that will be comfortable for users to navigate, and also SEO friendly.

Is the Wiki system good for our purpose? We are considering MediaWiki, is it a good choice? Any better alternative? (but free if possible).