Gain access to thousands of additional definitions and advanced search features—ad free! JOIN NOW
: one of the transitory somites of the head of an early vertebrate embryo
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:
Resources for head-cavity
Comments on head-cavity
What made you want to look up head-cavity? Please tell us where you read or heard it (including the quote, if possible).
the figure or shape of a crescent moon
Get Word of the Day daily email!
Late Autumn 2018 Words of the Day Quiz
Can you spell these 10 commonly misspelled words?
Test Your Knowledge - and learn some interesting things along the way.
Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!
What if your nickname became a dictionary entry?
Redundant but also not redundant
Wordies read on for enlightenment.
We hold back nothing in this article.
And is one way more correct than the others?
The story of an imaginary word that managed to sneak past our editors and enter the dictionary.
How to use a word that (literally) drives some people nuts.
The awkward case of 'his or her'
More word puzzles to rack your brain
SCRABBLE® fans, sharpen your skills!