variants: or prot-

Definition of proto-

1a : first in time protohistory
b : beginning : giving rise to protoplanet
2 : parent substance of a (specified) substance protactinium
3 : first formed : primary protoxylem
4 capitalized : relating to or constituting the recorded or assumed language that is ancestral to a language or to a group of related languages or dialects Proto-Indo-European

History and Etymology for proto-

Greek prōt-, prōto-, from prōtos; akin to Greek pro before — more at for

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