Ordovician
adjective
Or·do·vi·cian
ˌȯr-də-ˈvi-shən 
: of, relating to, or being the period between the Cambrian and the Silurian or the corresponding system of rocks see Geologic Time Table
Ordovician
noun
Examples of Ordovician in a Sentence
Recent Examples on the Web
The primary cause behind the Devonian and Ordovician mass extinction events is not fully understood, but both of them have also been linked to the depletion of Earth's ozone layer.
—
Sharmila Kuthunur, Space.com, 20 Mar. 2025
The Ordovician extinction killed 60 percent of marine invertebrates at a time when life was largely confined to the sea, while the late Devonian extinction wiped out around 70 percent of all species, including some of the earliest groups of fish found in the fossil record.
—David Bressan, Forbes, 17 Mar. 2025
Early plants like mosses and liverworts emerged around 470 million years ago during the Ordovician Period.
—Scott Travers, Forbes, 8 Dec. 2024
Other notably old objects include: Hundreds of fossils from the Late Ordovician period that are 420 million years old.
—Erin Couch, The Enquirer, 6 Oct. 2024
Of the over 200 impact craters known, 21 date to the Ordovician—the time period from 485.4 to 443.4 million years ago.
—David Bressan, Forbes, 23 Sep. 2024
The first clue came from a series of 21 craters that formed during a roughly 40-million-year period of intense meteorite impact known as the Ordovician impact spike.
—Margherita Bassi, Smithsonian Magazine, 19 Sep. 2024
Tomkins and his colleagues were intrigued by a window of time in the Ordovician period (~485-443 million years ago) where the rate of impacts seem to be higher on Earth based on the evidence of preserved craters.
—Erik Klemetti, Discover Magazine, 18 Sep. 2024
Around that time, during what’s called the Ordovician period, there seems to have been an increase in impact craters on Earth.
—Michael Irving, New Atlas, 16 Sep. 2024
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Sharmila Kuthunur, Space.com, 20 Mar. 2025
The Ordovician extinction killed 60 percent of marine invertebrates at a time when life was largely confined to the sea, while the late Devonian extinction wiped out around 70 percent of all species, including some of the earliest groups of fish found in the fossil record.
—David Bressan, Forbes, 17 Mar. 2025
Early plants like mosses and liverworts emerged around 470 million years ago during the Ordovician Period.
—Scott Travers, Forbes, 8 Dec. 2024
Other notably old objects include: Hundreds of fossils from the Late Ordovician period that are 420 million years old.
—Erin Couch, The Enquirer, 6 Oct. 2024
Of the over 200 impact craters known, 21 date to the Ordovician—the time period from 485.4 to 443.4 million years ago.
—David Bressan, Forbes, 23 Sep. 2024
The first clue came from a series of 21 craters that formed during a roughly 40-million-year period of intense meteorite impact known as the Ordovician impact spike.
—Margherita Bassi, Smithsonian Magazine, 19 Sep. 2024
Tomkins and his colleagues were intrigued by a window of time in the Ordovician period (~485-443 million years ago) where the rate of impacts seem to be higher on Earth based on the evidence of preserved craters.
—Erik Klemetti, Discover Magazine, 18 Sep. 2024
Around that time, during what’s called the Ordovician period, there seems to have been an increase in impact craters on Earth.
—Michael Irving, New Atlas, 16 Sep. 2024
Cite this Entry
“Ordovician.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Ordovician. Accessed 2 Jul. 2025.
Copy CitationKids Definition
Ordovician
adjective
Or·do·vi·cian
ˌȯrd-ə-ˈvish-ən
: of, relating to, or being a period of the Paleozoic era of geological history or the corresponding system of rocks see geologic time
Ordovician
noun
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