Bunting is a form of animal behavior, often found in cats, in which the animal butts or rubs their head against other things, including people. It is generally considered to be a form of territorial scent-marking behavior, where the cat rubs the scent glands on their cheeks and forehead on the object being marked.
Bunting is a normal animal behavior, and should be distinguished from head pressing, which is abnormal and typically a sign of illness.
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Bunting (animal behavior) Wikipedia(Text) CC BY-SA