Looking for good definers

In How to Read a Book, Mortimer J. Adler spends some time on the problem of, literally, "coming to terms" with an author. That is, making sure that we understand how he defines or uses certain words, because one person who writes about "love" may mean something different from another.

In Concerning the Teacher, St. Augustine says pretty much the same thing:

"He merely calls the thing about which he was thinking by a name which is other than the one by which we call it. We should agree with him at once if we could read his mind and see directly the thought which he was unable to express by the words spoken and the statement made. They say that definition can cure this error, so that in this case, if the speaker were to define what virtue is, it would be clear that the controversy is not about the thing but about the word. Now I may grant that this is so, but how often is it possible to find good definers?"