Almost look up to a liberal officer (7)
I believe the answer is:
Here is my best explanation:
'officer' is the definition.
(admiral is a kind of officer)
'almost look up to a liberal' is the wordplay.
'almost' means to remove the last letter (most of the word but not all of it).
'look up to' becomes 'admire' ('admire' can be a synonym of 'look up to').
'a liberal' becomes 'al' (I've seen this in other clues).
'admire' with its final letter taken away is 'admir'.
(Other definitions for admiral that I've seen before include "foremost in fleet", "[NELSON] perhaps", "Chief commander of fleet", "Navy bigwig", "Navy rank", "Senior naval officer", "Navy chief", "Red butterfly at sea?", "Rank" and "Officer".)