SINCE 1828

An Encyclopædia Britannica Company

Medical Dictionary

embryotoxon

play

noun em·bryo·tox·on \-ˈtäk-ˌsän, -sən\

Medical Definition of embryotoxon

: a congenital defect of the eye characterized by an opaque ring around the margin of the cornea

Seen and Heard

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

show

WORD OF THE DAY

alleviate

play

to relieve or lessen

Words at Play

watercolor-squares

We're Down With You Being—or Your Being?—a Square

It's about (you? your?) having your say.

Devilish Words

Don't blame a word use error on the devil.

alt-599492594f435

How 'Wonderful' Lost Its Sense of Wonder

A case of semantic bleaching

dog-covering-face

Don't Let Reading This Be Another 'Coulda' 'Shoulda' 'Woulda'

PSA: They're three separate words.

Ask the Editors

video-title-words-of-the-year-1066

Words of the Year: 1066

Or, Why Pig Meat is Called 'Pork' and Cow Meat is Called 'Beef'

How Often Is 'Biweekly'?

Don't get us started on 'bimonthly'

video-irregardless-grammar-peeve-blend-of-the-synonyms-irrespective-and-regardless

Irregardless

It is in fact a real word (but that doesn't mean you should use it).

video-moose-goose-weird-plurals

Weird Plurals

One goose, two geese. One moose, two... moose. What's up with that?

Word Games

time-traveler-quiz-which-word-came-first

Time Traveler Quiz: Which Word Came First?

Which word entered the English language first?

Take the quiz

Name More Food!

Test your knowledge of food vocabulary!

Take the quiz

Name That Thing

Name That Thing

Test your visual vocabulary with our 10-question challenge!

Take the quiz

SCRABBLE® Sprint

SCRABBLE® Sprint

SCRABBLE® fans, sharpen your skills!

Play the game