Slingshot missile (5)
I believe the answer is:
stone
'slingshot missile' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for stone that I've seen before include "Piece of rock - weight" , "that one will 26d at 8a [FLING at HIGHLAND GAMES]" , "Rock; cherry seed" , "Kernel" , "See 1" .)