Why is the Solar System called a system?

Answer 1

"System", in this sense, means there are different components that interact with one another.

I haven't checked this out, but it may be simply something to do with how words

were used centuries ago.

In the days when scientists were called "Natural Philosophers", it was common for

them to talk about the "system of the world".

By that they meant the motions of the planets and so on.

Galileo's most famous book was called:

"Dialogue Concerning the Two Chief World Systems".

He wrote about what we now call the "geocentric model" and the "heliocentric model".