Story includes fine sentence (4)
I believe the answer is:
life
'sentence' is the definition.
(life sentence in prison)
'story includes fine' is the wordplay.
'story' becomes 'lie' (story can mean a fabrication).
'includes' is an insertion indicator.
'fine' becomes 'f' (abbreviation in pencil classifications).
'lie' enclosing 'f' is 'LIFE'.
(Other definitions for life that I've seen before include "Birth to death" , "'While there's .... there's hope'" , "Animation" , "Existence - biography" , "and 12 Down: Biology, medicine, etc" .)