An organism that moves on its own and eats food is called an animal.

Here's why:

* Movement: Animals are able to move independently, unlike plants which are rooted in place. This allows them to search for food, escape predators, and explore their environment.

* Food Consumption: Animals are heterotrophic, meaning they obtain their energy by consuming other organisms (plants, animals, or fungi). This is in contrast to plants, which are autotrophic and produce their own food through photosynthesis.

Therefore, the defining characteristics of an animal are its ability to move independently and its reliance on consuming other organisms for nourishment.