Proterozoic
|pro-te-ro-zo-ic|
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/ˌproʊtərəˈzoʊɪk/
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/ˌprəʊtərəˈzɔɪ.ɪk/
earlier-life eon
Etymology
'Proterozoic' originates from New Latin and ultimately from Greek: Greek 'proteros' meaning 'earlier' + 'zoē' meaning 'life', combined with the adjectival suffix '-ic' (via scientific Latin/English formation).
'Proterozoic' was formed in scientific/Geological usage in New Latin from Greek roots and was adopted into English geological terminology in the late 19th to early 20th century to name a distinct geologic eon.
Initially built from elements meaning 'earlier life', the term evolved from a literal compound of those roots into the formal name of a geologic eon characterized by early complex life and atmospheric oxygenation.
Meanings by Part of Speech
Noun 1
a geological eon lasting from about 2.5 billion to 541 million years ago, after the Archean and before the Phanerozoic, characterized by the rise of atmospheric oxygen and the development of more complex single-celled and early multicellular life.
The Proterozoic saw major changes in Earth's atmosphere and life, including the Great Oxidation Event.
Adjective 1
relating to or characteristic of the Proterozoic eon (for example, Proterozoic rocks or Proterozoic fossils).
Proterozoic rocks in that region contain evidence of early oxygen-producing organisms.
Last updated: 2026/01/06 09:55