Identifying and eliminating keywords from the term list

if i change a keyword or eliminate one or several references with a unique keyword, but forget to take this keyword out of the terms list, then i will have a keayword without a result. It seems the update function only ADDS new keaywards to the terms list. Of course i could delete all keywords and then run an update. However, in some cases one would like to keep a standard keyword even if there is currently no reference to it.

It would therefore be great if there were a function to SEARCH THE TERM LIST FOR KEYWORDS NOT CURRENTLY FOUND IN ANY REFERENCE AND THEN DECIDE FOR EACH WHETHER TO ELIMINATE IT OR NOT.

Many thanks for your consideration

Armin