Plants & CreaturesGreek → English
Synapsid
/sɪˈnæpsɪd/noun
A member of the amniote lineage with a single opening behind each eye socket, a group that includes all mammals.
The Greek roots
σύν
sýn
together, with
ἁψίς
hapsís
arch, loop
Literally: “arches joined”
The story of the word
Henry Fairfield Osborn coined the term in 1903, sorting early amniotes by the holes in the sides of the skull. The name points at the bar of bone under the hole rather than the hole itself, an arch of cheek and temple. Every mammal alive is a synapsid, which is why calling the fossil forms "mammal-like reptiles" has the family relationship backwards.
- How it travelled
- Ancient Greek → scientific coinage → English
- First recorded
- 1903
Same family
diapsidsynapseapseapsis
In a sentence
Dimetrodon is a synapsid, and no closer to a dinosaur than you are.