Complaint about the French is pathetic (6)
I believe the answer is:
feeble
'pathetic' is the definition.
(thesaurus)
'complaint about the french' is the wordplay.
'complaint' becomes 'beef' (I've seen this before**).
'about' is a reversal indicator.
'the french' becomes 'le'.
'beef' backwards is 'feeb'.
'feeb'+'le'='FEEBLE'
'is' is the link.
(Other definitions for feeble that I've seen before include "Weak or Fragile" , "Very weak, without strength" , "Weak or ineffective" , "Weak, debilitated" , "rather weak" .)