is·​chi·​um | \ ˈi-skē-əm How to pronounce ischium (audio) \
plural ischia\ ˈi-​skē-​ə How to pronounce ischia (audio) \

Definition of ischium

: the lower and posterior of the three principal bones composing either half of the pelvis

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Other Words from ischium

ischial \ ˈi-​skē-​əl How to pronounce ischial (audio) \ adjective

Examples of ischium in a Sentence

Recent Examples on the Web Ribs, back and lower hips If all goes to plan, this second week will also see Sue lose its chest ribs, neck and chest backbones, and pubis and ischium (the lower hip bones). Steve Johnson And Phil Geib,, "The dismantling of Sue the T. rex at the Field Museum," 3 Feb. 2018

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

First Known Use of ischium

1646, in the meaning defined above

History and Etymology for ischium

Latin, hip joint, from Greek ischion

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Time Traveler for ischium

Time Traveler

The first known use of ischium was in 1646

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Cite this Entry

“Ischium.” Dictionary, Merriam-Webster, Accessed 28 Feb. 2020.

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More Definitions for ischium


is·​chi·​um | \ ˈis-kē-əm How to pronounce ischium (audio) \
plural ischia\ -​ə How to pronounce ischia (audio) \

Medical Definition of ischium

: the dorsal and posterior of the three principal bones composing either half of the pelvis consisting in humans of a thick portion, a large rough eminence on which the body rests when sitting, and a forwardly directed ramus which joins that of the pubis

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