Most employers have to stop (4)
I believe the answer is:
stem
'stop' is the definition.
(stem can mean to stop or interrupt)
'most employers have' is the wordplay.
'have' says the answer is hidden in the clue.
'STEM' is hidden in the letters of 'most employers'.
'to' acts as a link.
(Other definitions for stem that I've seen before include "Stop or slow the flow of" , "Restrain the flow of" , "part of vegetable?" , "Axis" , "Hold back - stock - check" .)