Dynamic instructions

We have a taxonomy (Classifications) that is a critical input for editors. Each classification has an associated description that tells the editor which kinds of posts can be assigned that classification. Currently editors must display the list of classifications and carefully review the description of each in order to set the classification properly. I would like to have this functionality embedded in the Post Edit screen.

Alternatives:

1. Display a new uneditable field that displays the taxonomy “description” once the editor has selected a taxonomy. This field would have to be next to the taxonomy field.
2. Display the ‘description’ text once the editor has selected the taxonomy.

I have no idea how to do this and I have no php knowledge.