His parents will be late (6)
I believe the answer is:
orphan
'his parents will be late' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
This is the entire clue.
Can you help me to learn more?
(Other definitions for orphan that I've seen before include "little Annie, maybe?" , "Child without parents" , "One who has lost both parents" , "Bereaved child" , "Child who has lost both parents" .)