a combining form meaning “earlier,” “before,” “former,” used in the formation of compound words: proterotype.
Also especially before a vowel, proter-.
Origin of protero-
< Greek, combining form representing próteros, comparative formed from pró; see pro-2
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for protero-
anterior or former in time, place, order, etcproterozoic
Word Origin for protero-
from Greek proteros fore
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012