Faithfulness and dependability (9)
I believe the answer is:
constancy
'faithfulness and dependability' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for constancy that I've seen before include "Devotion" , "Unvarying faithfulness" , "Firmness - faithfulness" , "The quality of being faithful and dependable" , "Faithfulness and dependability" .)