One giving guidance to a sanctimonious set? (5)
I believe the answer is:
pilot
'one giving guidance' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'a sanctimonious set?' is the wordplay.
'a sanctimonious' becomes 'pi'.
'set?' becomes 'lot' ('lot' can be a synonym of 'set').
'pi'+'lot'='PILOT'
'to' is the link.
Can you help me to learn more?
(Other definitions for pilot that I've seen before include "Guide, flyer" , "Navigator" , "Flier or helmsman" , "Driver of aircraft" , "Flier of aircraft" .)