Tease people in harmful act (7)
I believe the answer is:
torment
'tease' is the definition.
(I know that tease has the is a more specific form of the action torment)
'people in harmful act' is the wordplay.
'people' becomes 'men' (men are people).
'in' means one lot of letters goes inside another.
'harmful act' becomes 'tort' (tort is a kind of act. I am not sure about the 'harmful' bit.).
'men' put into 'tort' is 'TORMENT'.
Can you help me to learn more?
(Other definitions for torment that I've seen before include "Physical or mental pain" , "Severe physical or mental suffering" , "Tease unkindly" , "Harass" , "Torture" .)