Shiver? That's trembling, with little hesitation (7)
I believe the answer is:
shatter
'shiver?' is the definition.
(thesaurus)
'that's trembling with little hesitation' is the wordplay.
'trembling' indicates an anagram.
'with' says to put letters next to each other.
'little hesitation' becomes 'er'.
'thats' anagrammed gives 'shatt'.
'shatt'+'er'='SHATTER'
(Other definitions for shatter that I've seen before include "Break suddenly" , "Smash to pieces" , "thoroughly upset" , "Support for broken arm" , "Crack" .)