Fuddy-duddy endlessly causing confusion (3)
I believe the answer is:
fog
'confusion' is the definition.
(I know that fog is a type of confusion)
'fuddy-duddy endlessly' is the wordplay.
'fuddy-duddy' becomes 'fogy' (I've seen this in another clue).
'endlessly' means to remove the last letter.
'fogy' with its final letter removed is 'FOG'.
'causing' acts as a link.
(Other definitions for fog that I've seen before include "Obscure" , "Confusion" , "Heavy mist" , "Impenetrable mist" , "Bank restricting visibility" .)