Exaggeration, overstatement (9)
I believe the answer is:
hyperbole
I believe this clue is a double definition.
'exaggeration' is the first definition.
(I know that exaggeration can be written as hyperbole)
'overstatement' is the second definition.
(I know that overstatement can be written as hyperbole)
(Other definitions for hyperbole that I've seen before include "Exaggerated language, not meant literally" , "Exaggerated talk from boy helper" , "Deliberately extravagant exaggeration" , "not to be taken literally" , "The use of exaggeration for effect" .)