Definition of Archaeornithes
:a subclass of Aves comprising the earliest and most primitive of fossil birds, retaining distinctive reptilian characters, and including the two genera Archaeornis and Archaeopteryx
What's Trending Now
More Trending Words
Archaeornithes
plural noun
Ar·chae·or·ni·thes
\
-ˈȯrnəˌthēz
,
-ˌȯrˈnī(ˌ)thēz
\
Explore Merriam-Webster
There's more!
Love words? You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.
Start your free trial today and get unlimited access to America's largest dictionary, with:
- More than 250,000 words that aren't in our free dictionary
- Expanded definitions, etymologies, and usage notes
- Advanced search features
- Ad free!
Origin and Etymology of archaeornithes
New Latin, from archae- + -ornithes
Seen and Heard
What made you want to look up Archaeornithes? Please tell us where you read or heard it (including the quote, if possible).
Writing? Check your grammar now!