Is “Protoplanet” a Scrabble word?
Yes
PROTOPLANET
Valid in at least one Scrabble dictionary
Valid in these dictionaries
SOWPODS / CSW
Scrabble UK & International
TWL / NWL
Scrabble North America
Large English Dictionary
General English word list
Meaning of Protoplanet
noun
1.An astronomical object, approximately the size of the Moon, formed from the mutual gravitational attraction of planetesimals; they are thought to collide with each other and slowly form planets