Material heartless old jailer read aloud (6,3)
I believe the answer is:
turkey red
'material' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'heartless old jailer read aloud' is the wordplay.
'heartless' suggests removing the centre.
'old jailer' becomes 'turnkey' (historical term for a jailer).
'aloud' indicates a 'sounds like' (homophone) clue.
'turnkey' with its centre taken out is 'turkey'.
'read' is a homophone of 'red'.
'turkey'+'red'='TURKEY RED'
Can you help me to learn more?
(Another definition for turkey red that I've seen is " Textile dye".)