il·​i·​um | \ ˈi-lē-əm How to pronounce ilium (audio) \
plural ilia\ ˈi-​lē-​ə How to pronounce ilium (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 precious ilium gives reason to think the Antarctic climate of 40 million years ago was not unlike the one preferred by the helmeted frogs of Chile today. Alex Fox, Smithsonian Magazine, "Paleontologists Find Antarctica’s First Frog Fossil," 28 Apr. 2020 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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Cite this Entry

“Ilium.” Dictionary, Merriam-Webster, Accessed 17 Apr. 2021.

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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 ilium (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

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