Most definitely gone and done wrong instead? (5,4)
I believe the answer is:
stone-dead
'most definitely gone' is the definition.
'done wrong instead?' is the wordplay.
I cannot quite see how this works, but
an anagram of 'done' is 'oned' which is within the answer.
The remaining letters 'stead' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'and' is the link.
Can you help me to learn more?
(Other definitions for stone-dead that I've seen before include "Lifeless (as a rock?)" , "Completely lifeless" .)