Pivot to throw a six (4)
I believe the answer is:
axis
'pivot' is the definition.
(I've seen this before)
'throw a six' is the wordplay.
'throw' is an anagram indicator.
'a'+'six'='asix'
'asix' anagrammed gives 'AXIS'.
'to' acts as a link.
(Other definitions for axis that I've seen before include "line to be turned round" , "1936 alliance between Germany and Italy" , "Feasible" , "Imaginary line around which a body rotates" , "Imaginary dividing line" .)