Major or colonel, eg (7)
I believe the answer is:
officer
I believe this clue is a double definition.
'major' is the first definition.
(I've seen this before)
'colonel eg' is the second definition.
(colonel is a kind of officer)
(Other definitions for officer that I've seen before include "Military person in authority" , "Person with commission in armed services" , "Police constable" , "One holding post" , "General, for example" .)