synapsid
noun
syn·ap·sid
sə-ˈnap-səd 
: any of a subclass (Synapsida) of terrestrial vertebrates (such as the pelycosaurs and therapsids) having a single pair of lateral temporal skull openings
Note: Traditional classifications typically consider synapsids to be mammal-like, extinct reptiles ancestral to mammals. Cladistic classifications also consider these extinct forms ancestral to mammals but do not categorize them as reptiles.
synapsid
adjective
Examples of synapsid in a Sentence
Recent Examples on the Web
Researchers unearthed a large cache at the site, including the remains of ancient reptiles, amphibians and synapsids, the precursors to mammals.
—
Taylor Nicioli, CNN, 21 Mar. 2024
Life on land throughout the Permian Period, which lasted from about 298 million to 252 million years ago, was dominated by synapsids, the evolutionary precursors to mammals or protomammals.
—Jeanne Timmons, New York Times, 22 May 2023
Dimetrodon was a synapsid, sometimes called a proto-mammal or a mammal-like reptile.
—Gemma Tarlach, Discover Magazine, 31 May 2016
At the end of the Permian, there was a sort of bottleneck that caused only smaller synapsids to survive into the Triassic.
—John Wenz, Popular Mechanics, 22 Nov. 2018
Four-limbed vertebrates were becoming more diverse and among them were primitive amphibians, early reptiles and synapsids, the group that would one day include mammals.
—Fox News, 23 Jan. 2011
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Taylor Nicioli, CNN, 21 Mar. 2024
Life on land throughout the Permian Period, which lasted from about 298 million to 252 million years ago, was dominated by synapsids, the evolutionary precursors to mammals or protomammals.
—Jeanne Timmons, New York Times, 22 May 2023
Dimetrodon was a synapsid, sometimes called a proto-mammal or a mammal-like reptile.
—Gemma Tarlach, Discover Magazine, 31 May 2016
At the end of the Permian, there was a sort of bottleneck that caused only smaller synapsids to survive into the Triassic.
—John Wenz, Popular Mechanics, 22 Nov. 2018
Four-limbed vertebrates were becoming more diverse and among them were primitive amphibians, early reptiles and synapsids, the group that would one day include mammals.
—Fox News, 23 Jan. 2011
Dictionary Entries Near synapsid
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“Synapsid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/synapsid. Accessed 22 Dec. 2024.
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