Church keys groan when turned (5)
I believe the answer is:
organ
'church keys' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
'groan when turned' is the wordplay.
'groan' anagrams to 'ORGAN'.
But, I'm not clear how the anagram is indicated.
Can you help me to learn more?
(Other definitions for organ that I've seen before include "specialist magazine" , "daily?" , "Musical instrument - pancreas, perhaps" , "Wind instrument found in the body." , "Newspaper; instrument" .)