in situ

adverb or adjective

in si·​tu (ˌ)in-ˈsī-(ˌ)tü How to pronounce in situ (audio)
-ˈsi-,
-(ˌ)tyü How to pronounce in situ (audio)
 also  -ˈsē-,
-(ˌ)chü How to pronounce in situ (audio)
: 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 Testing methods include using immunohistochemistry and fluorescence in situ hybridization (FISH) to analyze the samples and determine genetic abnormalities.5 Part of the testing involves ruling out other genetic abnormalities including KRAS mutations, EGFR mutations, and ALK rearrangements. Benjamin Leach, Verywell Health, 23 Aug. 2023 More melanomas have been found, particularly those identified at the earliest stage, also known as stage 0 or melanoma in situ. Enrique Torchia, Fortune Well, 20 Aug. 2023 However, a recent study published after the task force recommendations showed that patients with melanoma in situ had a slight risk of death from melanoma, but lived longer than the average person. Enrique Torchia, Fortune Well, 20 Aug. 2023 As a brief afterword explains, Winchester worked on the book while hunkered down in his study in western Massachusetts during the coronavirus pandemic, unable to travel for in situ research. Michael Dirda, Washington Post, 4 May 2023 The scale of this in situ production will be staggering if the colony is truly to be considered self-sufficient. Joe Pappalardo, Popular Mechanics, 8 May 2023 It is fitted with a suite of remote sensing, geophysical and in situ instruments, including one led by NASA. Julia Musto, Fox News, 12 Apr. 2023 When picturing a piece of Wedgwood’s iconic Jasperware—the famous ceramics featuring white reliefs of Neoclassical figures and motifs laid over a duck-egg blue—in situ, what first springs to mind is probably a grand Regency townhouse in Bath, or a sprawling Palladian estate in Yorkshire. Liam Hess, Vogue, 30 June 2023 Her group is planning a vaccine study in women with a low-risk, noninvasive breast cancer called ductal carcinoma in situ. Carla K. Johnson, Chicago Tribune, 26 June 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'in situ.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Latin, in position

First Known Use

1740, in the meaning defined above

Time Traveler
The first known use of in situ was in 1740

Dictionary Entries Near in situ

Cite this Entry

“In situ.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/in%20situ. Accessed 29 Sep. 2023.

Kids Definition

in situ

adverb or adjective
in si·​tu (ˈ)in-ˈsī-t(y)ü How to pronounce in situ (audio)
-ˈsi-
: in the natural or original position
the cancer cells remained in situ
Etymology

Latin, "in position"

Medical Definition

in situ

adverb or adjective
in si·​tu
(ˈ)in-ˈsī-(ˌ)t(y)ü, -ˈsi- also -ˈsē-, -(ˌ)chü
: in the natural or original position or place
an in situ cancer confined to the breast duct
see carcinoma in situ
Last Updated: - Updated example sentences
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