Dear Sir or Madam,
I frequently run into words / terms I do not understand while reading emails. If this happens in Gmail or in Chrome, the problem is very easily solved: just double click on the word, Google will explain it in a yellow popup. This does not open a new browser tab or anything.
In eM right now, I can Google search or translate the entire email. Neither is quite what I am suggesting: a quick way to get explanation / further info (not necessarily translated into a new language or leave for my browser).
Hope you can give it some thoughts. Thanks.