The description of the Copy Editor badge currently says:
Edit 500 posts (excluding own or deleted posts and tag edits).
The term 'tag edit' is a bit ambiguous; what is meant here are edits to questions where only tags are changed ('retaggings'). If you change both the body (or the title) and the tags of a question, it does count towards the Copy Editor badge. Also, edits of tag wikis and tag excerpts count. For details and sources, see the FAQ entry.
Can we improve the wording? Something like
Edit 500 posts (excluding own or deleted posts and edits that only change tags).
which is still concise but unambiguous.