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headbutt is the most popular phrase on the web.

head-butt 1910,000 results on the web	headbutt 12,310,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
That violent head Gotta admit it was a naughty head butt made me understand many things. butt Wex. It was the result of a head butt. No, he didn't head butt.	We headbutt all the time, though. And the Mummy with a retaliatory headbutt. Because I wouldn't want to headbutt me or anything. Zidane, the headbutt in a moment. And if you touch me too much, God help me, I will headbutt you again. I'll give you a headbutt! Some of you might remember, it was Italy and France playing, and then Zidane at the end, the headbutt. Of course, what we witness here is a basic misunderstanding of the principle of the headbutt.

head-butt

1910,000 results on the web

headbutt

12,310,000 results on the web

More popular!

We headbutt all the time, though.
And the Mummy with a retaliatory headbutt.
Because I wouldn't want to headbutt me or anything.
Zidane, the headbutt in a moment.
And if you touch me too much, God help me, I will headbutt you again.
I'll give you a headbutt!
Some of you might remember, it was Italy and France playing, and then Zidane at the end, the headbutt.
Of course, what we witness here is a basic misunderstanding of the principle of the headbutt.