Stop for welcome morsel (8)
I believe the answer is:
prohibit
'stop' is the definition.
(I've seen this before)
'for welcome morsel' is the wordplay.
'for' becomes 'pro' (I've seen this before).
'welcome' becomes 'hi' (I've seen this in other clues).
'morsel' becomes 'bit' ('bit' can be a synonym of 'morsel').
'pro'+'hi'+'bit'='PROHIBIT'
(Other definitions for prohibit that I've seen before include "Bar" , "Stop" , "Ban; prevent" , "Proscribe, forbid" , "Forbid, ban" .)