plural noun
Si·​ren·​oi·​dei | \ ˌsīrə̇ˈnȯidēˌī\
variants: or less commonly Sirenoidea \ -​ēə \

Definition of Sirenoidei

in some classifications
: a group of lungfishes containing the genera Neoceratodus and Lepidosiren and some extinct forms from the Mesozoic

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!

History and Etymology for Sirenoidei

New Latin, from Latin siren + New Latin -oidei, -oidea

Keep scrolling for more

Comments on Sirenoidei

What made you want to look up Sirenoidei? Please tell us where you read or heard it (including the quote, if possible).


to make a payment or contribution

Get Word of the Day daily email!

Test Your Vocabulary

Time Traveler Quiz: Which Word Came First?

  • time traveler quiz which word came first
  • Which came first?
True or False

Test your knowledge - and maybe learn something along the way.

Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

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