Popular comprehensive, for the most part (2,7)
I believe the answer is:
in general
'for the most part' is the definition.
(thesaurus)
'popular comprehensive' is the wordplay.
'popular' becomes 'in'.
'comprehensive' becomes 'general' ('general' can be similar in meaning to 'comprehensive').
'in'+'general'='IN GENERAL'
(Other definitions for in general that I've seen before include "Not particularly" , "by and large" , "Largely" , "Overall" , "More-or-less" .)