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in situ

adverb or adjective
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in si·​tu | \ (ˌ)in-ˈsī-(ˌ)tü How to pronounce in situ (audio) , -ˈsi-, -(ˌ)tyü also -ˈsē-, -(ˌ)chü \

Definition of in situ

: in the natural or original position or place an in situ cancer confined to the breast duct

Examples of in situ in a Sentence

Recent Examples on the Web Upon her diagnosis of Stage 2B DCIS (ductal carcinoma in situ), Carolina Capellan got into her car and drove for hours. — Amanda Klarsfeld, sun-sentinel.com, "Mother’s breast cancer journey builds son’s character," 24 Oct. 2019 Brushes, drawing sticks and other implements are also in situ. — R. Daniel Foster, Los Angeles Times, "An L.A. home where homoerotic artist Tom of Finland lived is a shrine to his legacy," 2 Oct. 2019 The Stage 1 in situ tumor discovered in 2002 was readily treatable and caught early. — Loretta Waldman, courant.com, "Avon breast cancer survivor’s mother diagnosed too, 17 years later," 27 Sep. 2019 Most of the best is made here—take a tour of the Montelobos distillery to sample it in situ, or try one of the new local bars in town. — Mark Ellwood, Condé Nast Traveler, "Best Places to Visit in November," 20 Sep. 2019 Dennis was 36 in 2015 when she was diagnosed with the earliest form of breast cancer, called ductal carcinoma in situ, in which abnormal cells are found in milk ducts. — Meredith Cohn, baltimoresun.com, "Maryland regent, Baltimore lawyer dies of cancer in the middle of medical malpractice trial," 1 Sep. 2019 One spoke about nuclear power and nuclear thermal propulsion for spaceflight; one spoke about in situ resource utilization on the Moon and Mars; and one spoke about planetary exploration, the Dragonfly mission to Saturn’s moon Titan in particular. — Marsha Ivins, Time, "I'm a Retired Female Astronaut and I Can't Understand the Obsession With 'Gender Diverse' Space Crews," 28 Aug. 2019 She was diagnosed with ductal carcinoma in situ, the earliest version of breast cancer where abnormal cells are found in milk ducts. — Meredith Cohn, baltimoresun.com, "Patient with terminal cancer sues University of Maryland St. Joseph Medical Center over her care," 28 Aug. 2019 But here's the catch: The mirror would have to be made in situ. — Daniel Clery, Science | AAAS, "Could humanity’s return to the moon spark a new age of lunar telescopes?," 18 July 2019

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

1740, in the meaning defined above

History and Etymology for in situ

Latin, in position

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Time Traveler for in situ

Time Traveler

The first known use of in situ was in 1740

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Statistics for in situ

Last Updated

12 Nov 2019

Cite this Entry

“In situ.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/in%20situ. Accessed 14 December 2019.

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More Definitions for in situ

in situ

adverb or adjective
in si·​tu | \ (ˈ)in-ˈsī-(ˌ)t(y)ü, -ˈsi- also -ˈsē-, -(ˌ)chü \

Medical Definition of in situ

: in the natural or original position or place an in situ cancer confined to the breast duct — see carcinoma in situ

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