In this way or that, shut out! (4)
I believe the answer is:
thus
'in this way or that' is the definition.
'thus' can be an answer for 'in this way' (I've seen this in another clue). I am unsure of the rest of the definition.
'shut out' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'shut' with letters rearranged gives 'THUS'.
Can you help me to learn more?
(Other definitions for thus that I've seen before include "Like so" , "In this way" , "'So, therefore (4)'" , "Consequently" , "Therefore, hence" .)