What is the name for something on a dog's head? - briefly
The name for something on a dog's head is commonly referred to as "collar."
What is the name for something on a dog's head? - in detail
The term you are looking for is likely "collar." A collar is an accessory worn around a dog's neck, often used to hold identification tags or as a means of control and training. Collars come in various types, including flat collars, martingale collars, prong collars, and GPS tracking collars, each serving different purposes depending on the dog's needs and the owner's preferences. Additionally, some dogs may wear head halters or muzzles for specific training or safety reasons, but these are not typically referred to as collars.