proterozoic
1. [ adjective ] (geology) formed in the later of two divisions of the Precambrian era
Examples:

"proterozoic life forms"

Related terms: geology early
2. [ noun ] (geology) from 2,500 to 544 million years ago; bacteria and fungi; primitive multicellular organisms
Synonyms: proterozoic_aeon proterozoic_eon Preoterozoic_era
Related terms: eon era Precambrian
Similar spelling:   Proterochampsa