Cool when shaking dice (4)
I believe the answer is:
iced
'cool' is the definition.
('iced' can be similar in meaning to 'cool')
'shaking dice' is the wordplay.
'shaking' indicates anagramming the letters.
'dice' is an anagram of 'ICED'.
'when' acts as a link.
(Other definitions for iced that I've seen before include "Chilled - killed" , "Glazed" , "Covered with flavoured sugar topping" , "What cake might be" , "Kept cool" .)