The English word “planet” comes from the Ancient Greek word πλανήτης (planētēs), which means “wanderer.”

In Greek astronomy, planets were called “wanderers” because, unlike the fixed background stars, they visibly moved across the night sky over days and weeks. The noun πλανήτης is related to the Greek verb πλανάω / πλανᾶσθαι (planáō / planasthai), “to wander” or “to roam.” Through Latin (planeta), this word eventually became our modern English “planet.”