A dark place of retirement in France (5)
I believe the answer is:
unlit
'a dark' is the definition.
(I've seen this in another clue)
'place of retirement in france' is the wordplay.
I cannot quite see how this works, but
'in france' could be 'un' (I've seen this in other clues) and 'un' is found in the answer.
The remaining letters 'lit' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for unlit that I've seen before include "Dark, gloomy" , "Shady" , "not provided with a lamp?" , "Until (anag.)" , "Without illumination" .)