Mostly respect a Liberal naval officer (7)
I believe the answer is:
admiral
'naval officer' is the definition.
(commander of a naval fleet)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for admiral that I've seen before include "Top-ranking naval officer" , "(White or red) butterfly" , "Naval high-up" , "Supreme naval commander" , "Powerful sailor" .)