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Plants & CreaturesGreekEnglish

Therapsid

/θəˈræpsɪd/noun

A member of the synapsid group that contains mammals and their nearest extinct relatives.

The Greek roots

θήρ
thḗr
wild beast
+
ἁψίς
hapsís
arch, loop

Literally: beast arch

The story of the word

Robert Broom named the group in 1905 out of the Karoo fossils of South Africa, where the rock records the transition in unusual detail. The jaw is where the change shows: bones that hinged the reptilian jaw walk backwards into the ear and end up as the mammalian hammer and anvil. θήρ also reaches English as "treacle", by a long road through θηριακή, a compound antidote against the bite of a wild animal.

How it travelled
Ancient Greek → scientific coinage → English
First recorded
1905

Same family

synapsiddiapsidtheropodtreacle

In a sentence

Gorgonopsians were therapsids, and the sabre teeth arrived long before any cat.

Built on the same root

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