before vowels proter-, word-forming element meaning "former, earlier," from Greek proteros "before, former, anterior," from PIE *pro-, from root *per- (1) "forward" (hence "before, first").
Entries linking to protero-
*per- 1
Proto-Indo-European root forming prepositions, etc., meaning "forward," and, by extension, "in front of, before, first, chief, toward, near, against," etc.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit pari "around, about, through," parah "farther, remote, ulterior," pura "formerly, before," pra- "before, forward, forth;" Avestan pairi- "around," paro "before;" Hittite para "outside of," Greek peri "around, about, near, beyond," pera "across, beyond," paros "before," para "from beside, beyond," pro "before;" Latin pro "before, for, on behalf of, instead of," porro "forward," prae "before," per "through;" Old Church Slavonic pra-dedu "great-grandfather;" Russian pere- "through;" Lithuanian per "through;" Old Irish ire "farther," roar "enough;" Gothic faura "before," Old English fore (prep.) "before, in front of," (adv.) "before, previously," fram "forward, from," feor "to a great distance, long ago;" German vor "before, in front of;" Old Irish air- Gothic fair-, German ver-, Old English fer-, intensive prefixes.
Proterosaurus n.
also Protorosaurus, extinct genus of lizard-like reptiles first found fossilized in rocks from the late Permian in Germany and Britain, 1872, from Latinized form of Greek proteros "former, earlier" (see protero-) + sauros "lizard" (see -saurus). So called because it was long the earliest known fossil reptile.
Proterozoic adj.
1880, in geology, in reference to the period of the earliest fossil record of life on Earth, from protero- "former, earlier" + zoic "life." Now reckoned roughly as from 2,500 million years ago to 541 million years ago.