Expulsion of English diplomatic group (8)
I believe the answer is:
emission
'expulsion' is the definition.
(thesaurus)
'english diplomatic group' is the wordplay.
I cannot quite see how this works, but
'english' could be 'e' (abbreviation) and 'e' is found in the answer.
The remaining letters 'mission' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'of' acts as a link.
Can you help me to learn more?
(Other definitions for emission that I've seen before include "A giving out or putting forth" , "Process of giving out" , "it gets thrown out" , "radiation leakage?" , "Is in some (anag) - discharge" .)