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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
But only pieces likely to interest visitors are likely to remain in situ. Antonia Mortensen, CNN Money, 23 July 2025 While Liverpool have moved swiftly to add to their squad, there are a number of players already in situ whose futures are unclear. Andy Jones, New York Times, 11 June 2025 Miguel Molina, like Cuesta a young coach, 32, who is closer in age to the players and can bring a different kind of connection, remain in situ. Amy Lawrence, New York Times, 19 June 2025 In recent years, many researchers have been focused on DCIS: ductal carcinoma in situ, the earliest stage of cancer that in most cases remains in the milk ducts and does not invade other tissues. Alice Park, TIME, 12 Dec. 2024 See All Example Sentences for in situ

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

Browse Nearby Words

Cite this Entry

“In situ.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/in%20situ. Accessed 26 Jul. 2025.

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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