Train people to shun baboon (5)
I believe the answer is:
drill
'baboon' is the definition.
(drill is a kind of baboon)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for drill that I've seen before include "Instruct" , "Twill-weave cotton cloth" , "Tool; military training" , "Gimlet" , "Seed machine; baboon" .)