Inadequate way evidence sent back (8)
I believe the answer is:
pathetic
'inadequate' is the definition.
(thesaurus)
'way evidence sent back' is the wordplay.
I cannot really understand how this works, but
'way' could be 'path' (path is a kind of way) and 'path' is present in the answer.
'evidence' could be 'tic' (tic is a kind of evidence) and 'tic' is found within the answer.
A single letter 'e' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for pathetic that I've seen before include "Tip cheat - truly sad" , "Pitiable, inadequate" , "Lacking forcefulness" , "really pitiful" , "Miserably inadequate - way to tip cheat" .)