His wife will be late (7)
I believe the answer is:
widower
'his wife' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition. I also know that 'wife' relates to this answer.
'will be late' is the wordplay.
I cannot quite see how this works, but
'be' could be 'owe' (owing is a kind of being) and 'owe' is located in the answer.
'late' could be 'd' and 'd' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for widower that I've seen before include "Man who has lost his wife" , "former husband" , "Man left" , "Bereaved husband" , "Bereaved man" .)