Dad keeps ignoring Mr Martin Sheen (6)
I believe the answer is:
patina
'sheen' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'dad keeps ignoring mr martin' is the wordplay.
'dad' becomes 'pa' (synonyms).
'keeps' is an insertion indicator.
'ignoring' indicates named letters should be taken away.
'martin' with 'mr' removed is 'atin'.
'pa' enclosing 'atin' is 'PATINA'.
Can you help me to learn more?
(Other definitions for patina that I've seen before include "Distinctive surface acquired over time" , "Sheen acquired from constant handling" , "Fine layer on the surface, laid down over time" , "Surface film formed by age" , "well-worn surface" .)