Total doubly inaccurate? (3-3-3)
I believe the answer is:
out-and-out
'total' is the definition.
(I've seen this before)
'doubly inaccurate?' is the wordplay.
I cannot really understand how this works, but
'inaccurate?' could be 'out' (eg a calculation might be 'out') and 'out' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
(Other definitions for out-and-out that I've seen before include "Definitely" , "Absolute; completely" , "Thorough, surpassing" , "Thorough and complete - emphatically not indoors" , "In every respect" .)