SINCE 1828
dictionary
thesaurus
view recents

actinostome

noun
Save Word
ac·​tin·​o·​stome | \ ak-ˈti-nə-ˌstōm \
plural -s

Definition of actinostome

1 : the mouth of a radially symmetrical animal
2 : the peristome of an echinoderm

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!

First Known Use of actinostome

1860, in the meaning defined at sense 1

History and Etymology for actinostome

actin- + -stome

Keep scrolling for more

Learn More about actinostome

Time Traveler for actinostome

Time Traveler

The first known use of actinostome was in 1860

See more words from the same year

Statistics for actinostome

Cite this Entry

“Actinostome.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/actinostome. Accessed 2 Mar. 2021.

Style: MLA
MLA Chicago APA Merriam-Webster

Comments on actinostome

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

Show Comments  Hide Comments 

WORD OF THE DAY

organoleptic

Listen to the pronunciation of organoleptic

See Definitions and Examples »

Test Your Vocabulary

February 2021 Words of the Day Quiz

  • squirrel in winter
  • Which is a synonym of perdure?
True or False

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

TAKE THE QUIZ
Universal Daily Crossword

A daily challenge for crossword fanatics.

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