Puzzles man mentions are regularly diverse (9)
I believe the answer is:
mysteries
'puzzles' is the definition.
The definition and answer can be both related to communication as well as being plural nouns.
Maybe there's an association between them I don't understand?
'man mentions are regularly diverse' is the wordplay.
I cannot really understand how this works, but
'man' could be 'erie' and 'erie' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for mysteries that I've seen before include "in which priests classically played leading role" , "Messy rite incorporates puzzles" , "Phenomena that can't be explained" , "They're beyond understanding or explanation" , "They baffle understanding and cannot be explained" .)