periostracum

[ per-ee-os-truh-kuhm ]
/ ˌpɛr iˈɒs trə kəm /

noun, plural per·i·os·tra·ca [per-ee-os-truh-kuh]. /ˌpɛr iˈɒs trə kə/.

the external, chitinlike covering of the shell of certain mollusks that protects the limy portion from acids.

QUIZZES

IS YOUR VOCABULARY AS STRONG AS A HIGH SCHOOL STUDENT? TRY THIS QUIZ TO SEE!

It may seem like fun and games but this quiz that uses vocab from popular stories will determine how much you know.
Question 1 of 10
disgruntle

Origin of periostracum

1830–40; <New Latin, equivalent to peri-peri- + ostracum a shell <Greek óstrakon.See oyster

OTHER WORDS FROM periostracum

per·i·os·tra·cal, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for periostracum

  • Gray calls it the Periostracum, from the membranous skin covering the bones of quadrupeds.

    A Conchological Manual|George Brettingham Sowerby
  • The periostracum, or epidermis, is heavy and often velvety or even hairy.

    The Sea-beach at Ebb-tide|Augusta Foote Arnold