Better almost certainly to say nothing when questioned (7)
I believe the answer is:
surpass
'better' is the definition.
(I know that better can be written as surpass)
'almost certainly to say nothing when questioned' is the wordplay.
I cannot really understand how this works, but
'say' could be 'as' (I've seen this in other clues) and 'as' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for surpass that I've seen before include "Go one better" , "Exceed" , "supply best" , "Outdo" , "Outstrip" .)