In lock-up, notice English army group? (7)
I believe the answer is:
brigade
'army group?' is the definition.
(thesaurus)
'in lock-up notice english' is the wordplay.
I cannot quite understand how this works, but
'notice' could be 'ad' (both can mean an advertisement) and 'ad' is present in the answer.
'english' could be 'e' (abbreviation) and 'e' is found in the answer.
The remaining letters 'brig' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for brigade that I've seen before include "Rig a bed (anag)" , "Army unit" , "Army subdivision" , "Abridge (anag)" , "Army grouping" .)