Here's why:
* Proper nouns are specific: They refer to a unique individual, place, or thing. For example, "John" is a proper noun for a person, "Paris" is a proper noun for a city, and "The Great Gatsby" is a proper noun for a book.
* Toys are not unique: There are millions of toys of the same type. A "toy car" is not a unique object.
However, you can use proper nouns to describe specific toys:
* Brand names: "Barbie" (a specific doll), "Lego" (a specific type of building brick), "Hot Wheels" (a specific brand of toy cars).
* Characters: "Mickey Mouse" (a specific Disney character), "Batman" (a specific comic book character), "Pikachu" (a specific Pokémon character).
* Specific toys: "Mr. Potato Head" (a specific toy), "Teddy" (a specific teddy bear), "The Big Red Ball" (a specific ball).
So, while there's no proper noun for "toy" in general, you can use proper nouns to refer to specific types of toys, brands, or characters.