Cretan resident's maiden name found in letter to Greek city of old (8)
I believe the answer is:
minotaur
'cretan resident's maiden name found' is the definition.
I can't tell whether this defines the answer.
'letter to greek city of old' is the wordplay.
'letter' becomes 'a'.
'to' is a charade indicator (letters next to each other) (I've seen this in other clues).
'greek' becomes 'minot' (I am not sure about this - if you are sure you should believe this answer much more).
'city of old' becomes 'ur' (ancient Sumerian city).
'a' put after 'minot' is 'minota'.
'minota'+'ur'='MINOTAUR'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for minotaur that I've seen before include "Cretan labyrinth resident" , "50 per cent ruminant" , "Bull-headed Cretan monster" , "Monster, half bull and half man, slain by Theseus in Cretan labyrinth" , "Mythical man-bull" .)