Meaning of proto-

proto-

Pronunciation: [key]
  1. a combining form meaning “first,” “foremost,” “earliest form of,” used in the formation of compound words (protomartyr; protolithic; protoplasm), specialized in chemical terminology to denote the first of a series of compounds, or the one containing the minimum amount of an element.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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