Spread goodness, except Thursday (5)
I believe the answer is:
strew
'spread' is the definition.
(strewing is a kind of spreading)
'goodness except thursday' is the wordplay.
'goodness' becomes 'strewth' (both are expressions of shock).
'except' suggests deleting specific letters.
'thursday' becomes 'th' (common abbreviation).
'strewth' with 'th' removed is 'STREW'.
(Other definitions for strew that I've seen before include "Scatter untidily" , "Scatter, spread around" , "Scatter loosely" , "Sprinkle" .)