Telling stories — some only in Greek (5)
I believe the answer is:
'telling stories' is the definition.
(I've seen this before)
'some only in greek' is the wordplay.
'some' indicates the answer is hidden within the clue (some of the parts of the word are used).
'LYING' can be found hidden inside 'only in greek'.
(Other definitions for lying that I've seen before include "Prone - mendacity" , "Telling untruths" , "Deviating from truth" , "Prostrate -- prone" , "Flat-out" .)