The word planet comes from the Greek word meaning what?

The translation of "planet" is "wanderer". Unlike most stars, the planets appeared to drift around the sky relative to the other stars. They also occasionally (apparent retrograde motion) seemed to "double back" briefly before moving on again. Hence, "wanderers".

For the sake of clarity: the actual ancient Greek phrase from which the English Word "Planet" comes was "aster planetes", which means "wandering star." The modern Greek translation of English "planet" is "planetes".