German song wasn't truthful (4)
I believe the answer is:
lied
I believe this clue is a double definition.
'german song' is the first definition.
('song' in German)
'wasn't truthful' is the second definition.
(told a lie)
(Other definitions for lied that I've seen before include "Romantic song told a story" , "German air" , "Was economical with the truth" , "German romantic recital piece" , "Told untruths; song" .)