fe·​nes·​tra | \ fə-ˈne-strə How to pronounce fenestra (audio) \
plural fenestrae\ fə-​ˈne-​ˌstrē How to pronounce fenestrae (audio) , -​ˌtrī \

Definition of fenestra

1 : a small anatomical opening (as in a bone): such as
a or fenestra ovalis \ -​ō-​ˈvā-​ləs How to pronounce fenestra ovalis (audio) \ or fenestra vestibuli \ -​ve-​ˈsti-​byə-​ˌlī How to pronounce fenestra vestibuli (audio) \ : oval window
b or fenestra cochleae \ -​ˈkä-​klē-​ˌē How to pronounce fenestra cochleae (audio) , -​ˈkō-​klē-​ˌī \ or fenestra rotunda \ -​rō-​ˈtən-​də How to pronounce fenestra rotunda (audio) \ : round window
2 : an opening cut in bone

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Other Words from fenestra

fenestral \ fə-​ˈne-​strəl How to pronounce fenestral (audio) \ adjective

Examples of fenestra in a Sentence

Recent Examples on the Web Pterosaurs also had extra openings in their skulls, the largest of which was an opening in front of the eyes known as an antorbital fenestra. Michael B. Habib, Scientific American, "Pterosaurs Were Monsters of the Mesozoic Skies," 1 Oct. 2019 The massive dinosaur had two large holes in the roof of its skull (dorsotemporal fenestra) that were filled with muscles to aid jaw movements. Fox News, "T. rex had an 'air conditioner' in its head, study says," 6 Sep. 2019 The specialized pocket sits within an opening on the top rear of the skull called the dorsotemporal fenestra. Riley Black, Smithsonian, "Special Skull Windows Helped Dinosaur Brains Keep Cool," 4 Sep. 2019 All these animals are united by subtle skull features, such as the absence of a hole in the lower jaw called the mandibular fenestra and the flat, wrinkle-cusped teeth set along the jaws. Brian Switek, WIRED, "The Jurassic’s Housecat Croc," 6 June 2012

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fenestra.' 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 fenestra

circa 1737, in the meaning defined at sense 1

History and Etymology for fenestra

New Latin, from Latin, window

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Time Traveler for fenestra

Time Traveler

The first known use of fenestra was circa 1737

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Cite this Entry

“Fenestra.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fenestra. Accessed 15 Jul. 2020.

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More Definitions for fenestra


fe·​nes·​tra | \ fə-ˈnes-trə How to pronounce fenestra (audio) \
plural fenestrae\ -​ˌtrē How to pronounce fenestrae (audio) , -​ˌtrī How to pronounce fenestrae (audio) \

Medical Definition of fenestra

1 : a small anatomical opening (as in a bone): as
2a : a small opening cut in bone : window sense 2
b : a small opening in a surgical instrument (as an endoscope)

Other Words from fenestra

fenestral \ -​trəl How to pronounce fenestral (audio) \ adjective

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Rhyming Dictionary: Words that rhyme with fenestra

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