Some uncle; rich one in religious order (6)
I believe the answer is:
cleric
'religious order' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'some uncle rich one' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'CLERIC' is hidden within 'uncle rich one'.
'in' acts as a link.
Can you help me to learn more?
(Other definitions for cleric that I've seen before include "Church minister" , "Person ordained to the Christian ministry" , "Type of cloth, perhaps" , "Religious official" , "One ordained" .)