“Sylvius”

The following 2 entries include the term Sylvius.

aqueduct of Sylvius

noun

: a channel connecting the third and fourth ventricles of the brain

See the full definition

fissure of Sylvius

noun

: sylvian fissure

See the full definition

Word of the Day

Listen to the pronunciation of perfunctory

See Definitions and Examples »

Test Your Vocabulary

Which Came First?

  • baby chick with a brown egg
  • hot take or cold shoulder?
True or False

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

TAKE THE QUIZ
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.

Pick the best words!

PLAY
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
hangman letters and game
Hangman Lightning Round Figure out which word fits in the blanks.
See All