Plush toys are called "plushies" because of the material that they are made from. The word "plush" refers to a soft, luxurious fabric that has a raised nap or pile. This fabric is often used to make stuffed animals and other soft toys because of its soft and cuddly texture.

The use of the word "plushies" to refer to stuffed animals and other soft toys is believed to have originated in the 1990s within online communities such as fan groups and online forums. The term quickly caught on and became popular among collectors and enthusiasts of soft toys.

Nowadays, the term "plushie" is widely used to describe a wide range of soft toys, including stuffed animals, character toys, and other plush creations. It has become a popular term among fans of kawaii culture, which is a Japanese term for "cute" or "adorable" culture that has gained popularity around the world.

In short, plush toys are called "plushies" because of the soft, luxurious fabric they are made from, and the term has become popular within online communities and collector circles.