As it sounds, it is a title that has a 'complete' vocabulary list. Although we do make an effort to include every vocabulary card for the titles listed as "comprehensive", we do have our limits. We may not, for instance, include some abstruse vocabulary word that is found only in a single instance and nowhere else. (Then again, we might. We're mercurial like that.)

If we claim a term is not used in a particular book, and that title is a comprehensive type, and it is used in the same sense as one of our definitions, then we missed one. Shoot us an email and if we concur, we'll fix it.

It is not practical for us to include every vocabulary word for every single title listed on the site (it takes too much time and effort). Partial coverage implies that we are not attempting to collect every vocabulary word for that particular title. If a title gets enough support, however, we may recategorize a partial type to a comprehensive type.