Extend configuration of the pop-up window

Problem/Motivation

It would be a nice to have one or two configuration optional for the pop-up box.

The first one I think is a no-brainer, particularly for an educational setting where the user probably neither understands or cares for 'terms' as such and where 'What does this word mean?' or just 'Meaning' would be much more useful.

The latter might seem unnecessary since we can obviously theme it out but why render it at all if all we are going to do is hide it with CSS.