Shred a short book (4)
I believe the answer is:
atom
'shred' is the definition.
(thesaurus)
'a short book' is the wordplay.
'short' means to remove the last letter.
'book' becomes 'tome' (tome is a kind of book).
'tome' with its final letter taken away is 'tom'.
'a'+'tom'='ATOM'
(Other definitions for atom that I've seen before include "Very small object or amount" , "A mighty particle, can be explosive" , "A mighty particle, makes huge explosion" , "It was once thought to be smallest particle of matter" , "Minute particle" .)