Stop ignoring leader — relax! (4)
I believe the answer is:
ease
'relax' is the definition.
(eg to ease a restriction is to relax it)
'stop ignoring leader' is the wordplay.
'stop' becomes 'cease' (synonyms).
'ignoring leader' means to remove the first letter.
'cease' with its initial letter taken off is 'EASE'.
(Other definitions for ease that I've seen before include "Absence of effort" , "Absence of hardship" , "Leisure, relaxation" , "'Comfort, rest (4)'" , "Make less hard" .)