Being around one boring idiot leads to calumnies (10)
I believe the answer is:
aspersions
'calumnies' is the definition.
('aspersion' can be a synonym of 'calumny')
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for aspersions that I've seen before include "Slanders" , "derogatory remarks" , "slanderous accusations" .)