Nonsense that can sound just about OK (5)
I believe the answer is:
hokum
'nonsense' is the definition.
(hokum can mean nonsense or rubbish)
'can sound just about ok' is the wordplay.
I cannot really see how this works, but
'ok' is present in the answer.
'sound' could be 'hum' (humming is a kind of sounding) and 'hum' is located in the leftover letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'that' is the link.
Can you help me to learn more?
(Other definitions for hokum that I've seen before include "Meaninglessness" , "Sentimental stuff in play or film, nonsense" , "Rubbish" , "gammon" , "Bunk" .)