el·lip·soid | \i-ˈlip-ˌsȯid, e-\

Definition of ellipsoid 

: a surface all plane sections of which are ellipses or circles

Keep scrolling for more

Other Words from ellipsoid

ellipsoidal \i-ˌlip-ˈsȯi-dᵊl, (ˌ)e- \ or less commonly ellipsoid adjective

Examples of ellipsoid in a Sentence

Recent Examples on the Web

From radar observations, Psyche the asteroid appears ellipsoid in shape, about as wide as Massachusetts. Kenneth Chang, New York Times, "A Metal Ball the Size of Massachusetts That NASA Wants to Explore," 6 Jan. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ellipsoid.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of ellipsoid

1721, in the meaning defined above

Keep scrolling for more

Learn More about ellipsoid

Statistics for ellipsoid

Look-up Popularity

Time Traveler for ellipsoid

The first known use of ellipsoid was in 1721

See more words from the same year

More from Merriam-Webster on ellipsoid

See words that rhyme with ellipsoid

Britannica.com: Encyclopedia article about ellipsoid

Comments on ellipsoid

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


to reject or criticize sharply

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Roman Mythology Quiz

  • the-triumph-of-venus-by-alessandro-magnasco
  • Boreal comes from the name of the ancient Greek god of which wind?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

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!