Almost respect a line officer (7)
I believe the answer is:
admiral
'officer' is the definition.
(admiral is a kind of officer)
'almost respect a line' is the wordplay.
'almost' means to remove the last letter (most of the word but not all of it).
'respect' becomes 'admire' (admiring is a kind of respecting).
'a line' becomes 'al' (I am not sure about this - if you are sure you should believe this answer much more).
'admire' with its last letter taken off is 'admir'.
'admir'+'al'='ADMIRAL'
Can you help me to learn more?
(Other definitions for admiral that I've seen before include "Blake, for one" , "Supreme naval commander" , "Red butterfly in charge of the fleet" , "Red butterfly at sea?" , "Senior officer; mad liar (anag.)" .)