am·​ni·​ote | \ ˈam-nē-ˌōt How to pronounce amniote (audio) \

Definition of amniote

: any of a group (Amniota) of vertebrates that undergo embryonic or fetal development within an amnion and include the birds, reptiles, and mammals

Other Words from amniote

amniote adjective

Examples of amniote in a Sentence

Recent Examples on the Web The fossilized critter is an amniote—a land-dwelling vertebrate that lays eggs— and has four legs. Rasha Aridi, Smithsonian Magazine, 11 Nov. 2021 This fossil appears to be an early amniote, which is a land-living vertebrate that lays eggs, according to Adam Huttenlocker, an outside specialist on the team who researches early tetrapod fossils and is an assistant professor at USC. Sherry Liang, CNN, 5 Nov. 2021 This new kind of animal, that Dawson would name Hylonomus lyelli, remains the earliest amniote in the fossil record. Hillary Maddin, Smithsonian, 18 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'amniote.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of amniote

1878, in the meaning defined above

History and Etymology for amniote

New Latin Amniota, from amnion

Learn More About amniote

Time Traveler for amniote

Time Traveler

The first known use of amniote was in 1878

See more words from the same year

Dictionary Entries Near amniote



amniotic fluid

See More Nearby Entries 

Statistics for amniote

Cite this Entry

“Amniote.” Dictionary, Merriam-Webster, Accessed 9 Aug. 2022.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon


Test Your Vocabulary

The Great British Vocabulary Quiz

  • union jack speech bubble
  • Named after Sir Robert Peel, what are British police called?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!