Part of UK greeting schedules for extreme sceptics (9)
I believe the answer is:
nihilists
'extreme sceptics' is the definition.
The answer and definition can be both people as well as being plural nouns.
Maybe you can see an association between them that I don't see?
'part of uk greeting schedules' is the wordplay.
'part of uk' becomes 'ni' (Northern Ireland).
'greeting' becomes 'hi' (hi is a kind of greeting).
'schedules' becomes 'lists'.
'ni'+'hi'+'lists'='NIHILISTS'
'for' is the link.
Can you help me to learn more?
(Other definitions for nihilists that I've seen before include "They reject all theories of morality or religious belief" , "Old revolutionaries" , "unbelievers" .)