Studious group of assorted marines (7)
I believe the answer is:
seminar
'studious group' is the definition.
The answer and definition can be both groups as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'assorted marines' is the wordplay.
'assorted' indicates anagramming the letters.
'marines' with letters rearranged gives 'SEMINAR'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for seminar that I've seen before include "Teaching meeting, conference" , "Discussion meeting" , "Meeting for study" , "Group discussion of subject" , "Meeting for exchange of ideas" .)