yolk-sac placenta


Definition of yolk-sac placenta 

: a structure in some sharks resembling a placenta, consisting of the vascular embryonic yolk sac wall intimately associated with the vascular maternal uterine or oviducal wall, and serving to nourish the embryo

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!

Learn More about yolk-sac placenta

Share yolk-sac placenta

Statistics for yolk-sac placenta

Look-up Popularity

Comments on yolk-sac placenta

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


something that serves to warn or remind

Get Word of the Day daily email!

Test Your Vocabulary

Difficult Vocab Quiz

  • the-education-of-achilles-eugne-delacroix
  • Which is a synonym of discomfit?
Spell It

Can you spell these 10 commonly misspelled words?

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!