Merriam-Webster Logo
SINCE 1828
Menu
dictionary thesaurus

endostracum

noun
end·​os·​tra·​cum
plural endostraca\ -​kə \

Definition of endostracum

: the inner layer of a shell especially of a crustacean

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 endostracum

New Latin, from end- + Greek ostrakon hard shell; akin to Greek osteon bone

Keep scrolling for more

Learn More about endostracum

Statistics for endostracum

Look-up Popularity

Comments on endostracum

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

Show Comments  Hide Comments 

WORD OF THE DAY

demeanor

Listen to the pronounciation of demeanor

behavior toward others

Get Word of the Day daily email!

Test Your Vocabulary

Words for Summer: A Quiz

  • a closeup of a sunflower
  • Which of the following words means “of or relating to summer”?
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
SCRABBLE® Sprint

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

TAKE THE QUIZ
Love words? Need even more definitions?

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

Words at Play
Ask the Editors
Word Games