Military officer in swamp with a rear admiral (7)
I believe the answer is:
marshal
'military officer' is the definition.
(I know that general are military)
'swamp with a rear admiral' is the wordplay.
'swamp' becomes 'marsh' (I've seen this before).
'with' says to put letters next to each other.
'a rear admiral' becomes 'al' (I can't explain this - if you can you should believe this answer much more).
'marsh'+'al'='MARSHAL'
'in' is the link.
Can you help me to learn more?
(Other definitions for marshal that I've seen before include "High officer" , "Assemble and arrange" , "Arrange in order" , "put in order" , "Muster" .)