Some knock erratic Aussie oaf (5)
I believe the answer is:
ocker
'oaf' is the definition.
Both the definition and answer are singular nouns.
Maybe there's an association between them I don't understand?
'some knock erratic aussie' is the wordplay.
'some' indicates the answer is hidden within the clue (some of the parts of the word are used).
'OCKER' can be found hidden inside 'knock erratic aussie'.
Can you help me to learn more?
(Other definitions for ocker that I've seen before include "Australian" , "Boorish" , "oafish Aussie" .)