Dentist’s tool (5)
I believe the answer is:
drill
'dentist's tool' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for drill that I've seen before include "Bore (a hole); fabric" , "Instruct" , "Rehearsal of the procedure to be followed in an emergency" , "DIY tool" , "Rehearsal; boring tool" .)