Bottle wearing ensign? (6)
I believe the answer is:
flagon
'bottle' is the definition.
(I've seen this before)
'wearing ensign?' is the wordplay.
I cannot quite understand how this works, but
'ensign?' could be 'flag' ('flag' can be a synonym of 'ensign') and 'flag' is present in the answer.
The remaining letters 'on' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for flagon that I've seen before include "Large drinks container" , "Large bottle for alcohol" , "Large vessel for beverages" , "Drinking vessel" , "Snow White companion" .)