Training; bore (5)
I believe the answer is:
drill
This clue is a double definition.
'training' is the first definition.
(I know that drill is a type of training)
'bore' is the second definition.
(bore can mean to drill into something)
(Other definitions for drill that I've seen before include "Boring machine" , "Put a hole in" , "it could get boring" , "Square-bashing" , "strong twilled cotton" .)