They all have their day on Nov. 2 (5)
I believe the answer is:
'they' is the definition.
Both the answer and definition are plural nouns.
Perhaps there's a link between them I don't understand?
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for souls that I've seen before include "All --, Oxford college" , "People" .)