Gobbledygook? Of course it's not! (8)
I believe the answer is:
nonsense
'gobbledygook?' is the definition.
(thesaurus)
'course it's not' is the wordplay.
I cannot really see how this works, but
'course' could be 'se' and 'se' is found within the answer.
'not' could be 'non' (I've seen this in other clues) and 'non' is located in the answer.
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is present in the answer.
This may be the basis of clue (or it may be nonsense).
'of' is the link.
Can you help me to learn more?
(Other definitions for nonsense that I've seen before include "Hokum, hogwash" , "Claptrap, hogwash" , "Cobblers" , "hot air" , "Rubbish, twaddle" .)