名詞 proterozoic:

1. from 2,500 to 544 million years ago; bacteria and fungi; primitive multicellular organisms
   同義詞：Proterozoic eon, Proterozoic aeon

形容詞 proterozoic:

1. formed in the later of two divisions of the Precambrian era

Prot.er.o.zo.ic

adj.（形容詞）
Of, belonging to, or being the later of two divisions of Precambrian time, during which sponges, sea worms, and other forms of sea life appeared.
原生代的，元古代的：前寒武紀(jì)兩個(gè)時(shí)期中的后一個(gè)時(shí)期的，屬于這個(gè)時(shí)期的，在這個(gè)時(shí)期的在這個(gè)時(shí)期海綿、海洋蠕蟲和其它形式的海洋生命出現(xiàn)
n.（名詞）
The Proterozoic Era.
原生代，元古代

來(lái)源：
Greek proteros [earlier, former] * see per
希臘語(yǔ) proteros [更早的，以前的] *參見(jiàn) per
-zoic
-zoic