Disrupt loud pastime (4)
I believe the answer is:
ludo
'pastime' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'disrupt loud' is the wordplay.
'disrupt' indicates anagramming the letters.
'loud' with letters rearranged gives 'LUDO'.
Can you help me to learn more?
(Other definitions for ludo that I've seen before include "race for four tokens" , "Children's board game" , "Game (meaning 'I play' in Latin)" , "Traditional board game" , "Type of board game" .)