spir·​u·​la | \ ˈspir(y)ələ \

Definition of spirula

1 capitalized : a genus (coextensive with a family Spirulidae of the order Decapoda) of small cephalopods related to the extinct belemnites, having a many-chambered shell coiled freely in a flat spiral that is comparable to the phragmocone of the belemnite shell and almost enveloped in the soft parts, and occurring in most tropic seas usually at great depths from which the shells float to the surface and are cast on beaches, although complete specimens of the animal are rare
2 plural -s : a cephalopod of the genus Spirula

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 spirula

New Latin, from Late Latin, twisted cracknel, from Latin spira coil, twist + -ula

Keep scrolling for more

Learn More about spirula

Statistics for spirula

Cite this Entry

“Spirula.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/spirula. Accessed 16 Apr. 2021.

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

Comments on spirula

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


Test Your Vocabulary

The Exceptions Quiz III

  • one green toy robot amidst many red toy robots
  • Which of these words does not mean "nonsense"?
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!