Employed by some pious educators (4)
I believe the answer is:
used
'employed' is the definition.
('use' can be a synonym of 'employ')
'some pious educators' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'USED' can be found hidden inside 'pious educators'.
'by' acts as a link.
(Other definitions for used that I've seen before include "Exploited group" , "Was treating" , "not got directly" , "Second-hand - not wasted" , "Employed - exploited" .)