Tease outsiders hurt in training? (8)
I believe the answer is:
teaching
'training?' is the definition.
(training is a kind of teaching)
'tease outsiders hurt' is the wordplay.
'outsiders' means to remove the middle letters (only the letters on the outside of the word remain).
'hurt' becomes 'aching' (I can't justify this - if you can you should give a lot more credence to this answer).
'tease' with its centre removed is 'te'.
'te'+'aching'='TEACHING'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for teaching that I've seen before include "Instructing" , "exercise ..." , "Training" , "Imparting skills or knowledge" , "Educating" .)