a combining form meaning “earlier,” “before,” “former,” used in the formation of compound words: proterotype.
Also especially before a vowel, proter-.
Compare proto-.

Origin of protero-

< Greek, combining form representing próteros, comparative formed from pró; see pro-2 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for protero-


combining form

anterior or former in time, place, order, etcproterozoic

Word Origin for protero-

from Greek proteros fore
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