Could such a widow make hay? (5)
I believe the answer is:
grass
'hay?' is the definition.
(thesaurus)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for grass that I've seen before include "blow the gaff" , "Narrow-leaved green herbage" , "Lawn plant" , "German author" , "Turf" .)