Etymology of the English word protoplanet
the English word protoplanet
using the English prefix proto-
derived from the English word planet
derived from the Old French word planete
derived from the Latin word planeta (planet)
derived from the Greek word planetes, πλανήτης (a rover ('planet'); an erratic teacher)
derived from the Greek word planes
derived from the Greek word planasthai
derived from the Proto-Indo-European root *pelə-
derived from the Greek word planao, πλανάω (to (properly, cause to) roam (from safety, truth, or virtue))