Archosauria

Part of speech: noun

Definitions

1. A clade of reptiles that includes dinosaurs and modern birds, characterized by specific skeletal features and evolutionary lineage
2. A group of amniotes distinguished by particular traits, encompassing all dinosaurs and birds, as well as their extinct relatives
3. A major lineage of reptiles characterized by a unique set of anatomical adaptations, consisting of both extinct species and their living descendants like birds

Etymology: Archosauria was coined in 1866 by the English palaeontologist Harry Govier Seeley, who needed a name for a grouping of reptiles that included crocodiles, dinosaurs and their relatives. The term combines the Greek "arkhos", meaning "ruler" or "chief", with "sauros", meaning "lizard". Seeley meant "ruling reptiles", a name that reflected how dominant this lineage was during the Mesozoic era, when dinosaurs and their cousins held most land and sea niches. The name has aged better than the idea behind it. Seeley's grouping was not itself a natural family tree in the modern sense, and the modern use of the term refers to the clade containing crocodilians and birds along with their extinct relatives. The Greek elements were chosen by a Victorian scientist building a Latinised name from classical roots, so, like most scientific coinages of that era, it looks ancient without being one.

Synonyms: archosaurs