Unsightly vessel in a pig pen? (6)
I believe the answer is:
spotty
'unsightly' is the definition.
Both the answer and definition are adjectives. Perhaps you can see an association between them that I can't see?
'vessel in a pig pen?' is the wordplay.
'vessel' becomes 'pot' (type of container).
'in' indicates putting letters inside.
'a pig pen?' becomes 'sty' (where pigs are kept).
'pot' put within 'sty' is 'SPOTTY'.
Can you help me to learn more?
(Other definitions for spotty that I've seen before include "covered in pimples" , "Covered in acne" , "Pimply or covered with dots" , "irregular" , "Covered in rash" .)