ultradian

adjective
ul·tra·di·an | \ əl-ˈtrād-ē-ən \

Medical Definition of ultradian 

: being, characterized by, or occurring in periods or cycles (as of biological activity) of less than 24 hours and often repeated frequently (as every 90 minutes) throughout a 24-hour period — compare circadian, infradian

Learn More about ultradian

Comments on ultradian

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

WORD OF THE DAY

to deposit or conceal in a hiding place

Get Word of the Day daily email!

Test Your Vocabulary

Name that Food Quiz

Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.

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!