il·​i·​um | \ ˈi-lē-əm How to pronounce ilium (audio) \
plural ilia\ ˈi-​lē-​ə How to pronounce ilia (audio) \

Definition of ilium

: the broad, dorsal, upper, and largest of the three principal bones composing either half of the pelvis

Examples of ilium in a Sentence

Recent Examples on the Web The ilium looks like those of a living group of frogs called the helmeted frogs. Lucas Joel, New York Times, "Fossil Shows Cold-Blooded Frogs Lived on Warm Antarctica," 23 Apr. 2020 The last bones to go, the ilium and sacrum (the big hip bones atop the skeleton) are the heaviest bone structure. Steve Johnson And Phil Geib,, "The dismantling of Sue the T. rex at the Field Museum," 3 Feb. 2018 Conclusion: Ilium can be quite difficult to master. Jonathan H. Liu, WIRED, "Unearthing Treasures: Pergamon and Ilium," 14 June 2011

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

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First Known Use of ilium

1706, in the meaning defined above

History and Etymology for ilium

New Latin, alteration of Latin ilia

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Time Traveler for ilium

Time Traveler

The first known use of ilium was in 1706

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Statistics for ilium

Last Updated

1 Jun 2020

Cite this Entry

“Ilium.” Dictionary, Merriam-Webster, Accessed 6 Jun. 2020.

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More Definitions for ilium


il·​i·​um | \ ˈil-ē-əm How to pronounce ilium (audio) \
plural ilia\ -​ē-​ə How to pronounce ilia (audio) \

Medical Definition of ilium

: the dorsal, upper, and largest one of the three bones composing either lateral half of the pelvis that in humans is broad and expanded above and narrower below where it joins with the ischium and pubis to form part of the acetabulum

More from Merriam-Webster on ilium

Rhyming Dictionary: Words that rhyme with ilium Encyclopedia article about ilium

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