headbutt
noun
[ ˈhɛdbʌt ]
• an aggressive and forceful thrust with the top of the head into the face or body of another person.
• "he tries a headbutt, which I dodge"
headbutt
verb
• attack (someone) with a headbutt.
• "while I have him by the lapels I headbutt him across the face"
butt heads
• engage in conflict or be in strong disagreement.
