23 down
9
heats
won’t
start
(4)
9 heats won’t start (4)
hints
0
checks
0
hints
The definition is at the beginning of the clue.
How the clue works
The 9 is a cross-reference to 9 across (RACE), so the answer pairs with it to give the phrase 'arms race'. The wordplay takes WARMS (a word meaning heats) and removes its start (W), leaving ARMS.