Facet of an issue (6)
I believe the answer is:
aspect
'facet of an issue' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for aspect that I've seen before include "Feature; appearance" , "Distant view of a wide area" , "'View, perspective (6)'" , "Visual effect" , "View or facet" .)