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Plants & CreaturesGreekEnglish

Diapsid

/daɪˈæpsɪd/noun

A member of the reptile lineage with two openings behind each eye socket, including lizards, snakes, crocodiles and birds.

The Greek roots

δι-
di-
two, twice
+
ἁψίς
hapsís
arch, loop

Literally: two arches

The story of the word

Osborn named it alongside synapsid in 1903, counting the windows in the skull. Turtles wrecked the tidy scheme for a century by having none at all, until DNA placed them inside the diapsids anyway, their openings lost somewhere along the way. Birds are diapsids too, so a good half of the group is currently overhead.

How it travelled
Ancient Greek → scientific coinage → English
First recorded
1903

Same family

synapsidsynapseapseapsis

In a sentence

The two temporal openings mark the skull as diapsid at a glance.

Built on the same root

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