To intentionally annoy and upset someone by making unkind remarks to them, laughing unkindly, etc. (Cambridge Dictionary)
To reproach or challenge in a mocking or insulting manner : jeer at (Merriam – Webster)
A remark made in order to anger, wound, or provoke someone. (Oxford Dictionaries)
‘Smash ultimate’ taunts: How to provoke your opponents.
Why do people want to taunt others?