This is a nice site featuring the possibilities in a wide variety of languages (including Klingon!). In general, people were aware of the planets out to and including Saturn, but not beyond. Words for Uranus, Neptune, and Pluto are based either on the living languages adoption of terms or the names of the gods who lent their names to these planets after discovery.

In opposition, Uranus is on the limits of visibility for people with extraordinarily good eyesight, but it is so dim and slow moving from the earth point of view that it was not recognized as wandering across the star field until after the invention of the telescope.