Why our planet is called Earth?

I bet you have asked yourself this question once, even when a child. If you asked you mother and she told you: "because yes", now you're finally going to find out the answer. Even our planet being almost entirely (70%) covered by water, it's still its name "Earth". Some centuries ago, there was no information about Earth's geography. People even used to think the planet was a square. I can tell there was no chance to travel all around the world to discover that 70% is water. They used to call Earth the place where was located their habitation. The word comes from latin ters, and it means human life. Every location possible to be habitated was called earth. As you can tell, the term has been world wide spreaded and it's how you call your home nowadays. Furthermore, if all the water is pulled together as a sphere and a comparison is made between the earth proportion and the water sphere, there would be no doubts about the small portion of water that exists in our planet.