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The Structure of the Words

Ancient Latin and Greek

The language of the Geologic Time Chart is ancient Latin and Greek. These two ancient languages are used in science because they are no longer spoken, evolving languages, and as such will retain the exact meaning of the words through time. Also, since the Medieval Ages Latin and Greek were the languages of science. Early scientists communicated with one another using Latin and Greek as international languages. In modern times, the use of Latin and Greek retains this internationality as the languages are used to designate scientific terms that are understood by everyone on the scientific community.

So what do the names of the Eons, Eras, Periods, and Epochs really mean?


Hadean Eon ~ Hadean is Greek for Beneath the Earth.

Archean Eon ~ Archean is Greek for Ancient.

Proterozoic Eon ~ Proterozoic is Greek for Former.
                                        Zoic is Greek for Life.
                                        Proterozoic means Former Life.

Phanerozoic Eon ~ Phanero is Greek for Visible.
                                          Zoic is Greek for Life.
                                          Phanerozoic means Visible Life.


Paleozoic Era ~ Paleo is Greek    for Old.
        Paleozoic means Old Life.

Mesozoic Era ~ Meso is Greek    for Middle.
         Mesozoic means Middle Life.

Cenozoic Era ~ Ceno is Greek for New.
                                    Cenozoic means New Life.


Paleozoic Era Periods

Cambrian Period ~ Cambria is the Latin / Roman name for Wales in Great Britain.

Ordovician Period ~ Ordovices is the Latin / Roman name
   for a Celtic Tribe in Wales.

Silurian Period ~ Silures is the Latin / Roman name for
   a Celtic Tribe in Wales.

Devonian Period ~ Named after Devonshire in Southwest    Great Britain.

Mississippian Period ~ Named after the State of Mississippi.

Pennsylvanian Period ~ Named after the State of Pennsylvania.

Permian Period ~ Named after the Province of Perm, Russia.

Mesozoic Era Periods

Triassic Period ~ Tri is Latin for Three. Named after threefold division of rocks in Germany.

Jurassic Period ~ Named for the Jura Mountains in Switzerland.

Cretaceous Period ~ Creta is Latin for Chalk. Named for the chalk cliffs of Dover in Great Britain.

Cenozoic Era Periods

Tertiary Period ~ Named derived from earlier Geologic Time Chart that used a fourfold division of rocks.

Quaternary Period ~ Named derived from earlier Geologic Time Chart that used a fourfold division of rocks.

Cenozoic Era Epochs

Tertiary Period

Paleocene Epoch ~ Greek meaning Early Dawn of the Recent.

Eocene Epoch ~ Greek meaning Dawn of the Recent.

Oligocene Epoch ~ Greek meaning Slightly Recent.

Miocene Epoch ~ Greek Meaning Less Recent.

Pliocene Epoch ~ Greek Meaning More Recent.

Quaternary Period

Pleistocene Epoch ~ Greek Meaning Most Recent.

Holocene Epoch ~ Greek Meaning Wholly Recent.

Latin & Greek Quiz

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