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sen·​ti·​nel ˈsent-nəl How to pronounce sentinel (audio)
: sentry


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sentineled or sentinelled; sentineling or sentinelling

transitive verb

: to watch over as a sentinel
: to furnish with a sentinel
: to post as sentinel

Examples of sentinel in a Sentence

Noun a lone sentinel kept watch over the fort
Recent Examples on the Web
Ever since, evidence of these ancient plant sentinels has been in short supply. Wire Service, The Mercury News, 3 Feb. 2024 On the second largest of the seven remote islands, historic Fort Jefferson stands like a sentinel over the sand. Southern Living Editors, Southern Living, 16 Jan. 2024 Launched on September 5th, 1977, the spacecraft reached Neptune, the outer sentinel of the Solar System, over a decade later. Paul Sutter, Ars Technica, 10 July 2023 Seabirds are highly sensitive to changing ocean conditions and prey availability, earning them a reputation as sentinels of the sea. Abby McBride, Smithsonian Magazine, 19 Dec. 2023 The ruins of Cine Ópera, a now-defunct art deco cinema, stand like a sentinel at San Rafael's northern edge. Michael Snyder, Travel + Leisure, 27 Nov. 2023 The idea of using plants as environmental sentinels isn’t new. WIRED, 30 Oct. 2023 And then, one afternoon, Cynthia and I saw, perched like sentinels in the oaks surrounding the house, hawks. Martha McPhee, The New Yorker, 19 Aug. 2023 The have been referred to as lakeshore sentinels, offering waypoints on water and markers on land, and come in all shapes and sizes. Frank Witsil, Detroit Free Press, 7 Aug. 2023
Think delicate epiphytic orchids curling around the knobby trunks of waving palms; white clapboard cottages with shutters in shades of salmon, sunshine, and seafoam; and a stretch of private beach with a lighthouse sentinel on the horizon. Caroline Rogers, Southern Living, 30 June 2023 The home's two eponymous wooden lions sit sentinel out front. Genevieve Redsten, Journal Sentinel, 9 June 2023 Following the logic, sentinel behavior resulting from varied chronotypes would have made early human groups both safer during the night and better prepared, cognitively, for whatever the day brought. Gemma Tarlach, Discover Magazine, 11 July 2017 However, sentinel surveillance data suggests that there hasn't been an unusual rise. Beth Mole, Ars Technica, 7 Dec. 2022 However, on the wall there is only an enormous and exceedingly bad painting, in a heavy wooden frame, done primarily in weary shades of brown, depicting a Tuscan landscape with dim saints and sentinel cypresses and an unidentifiable bird on a bough. John Banville, The New York Review of Books, 6 Apr. 2022 This clinical strategy relies both on infected individuals coming to sentinel hospitals and medical authorities who are influential and persistent enough to raise the alarm. Maureen Miller, The Conversation, 1 June 2021 Expanding Centers for Disease Control and Prevention sentinel surveillance programs and other surveillance programs to offer tests not only to those who ask but also to those who may not know to ask is also on Biden's Plan to Combat Coronavirus. USA Today, 2 Nov. 2020 And there are certain types of events or sentinel events that require a deeper dive before continuing to ensure the safety of current and future participants. Adrian Hernandez, STAT, 14 Oct. 2020 See More

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

Word History



Middle French sentinelle, from Old Italian sentinella, from sentina vigilance, from sentire to perceive, from Latin

First Known Use


1579, in the meaning defined above


1593, in the meaning defined at sense 1

Time Traveler
The first known use of sentinel was in 1579

Dictionary Entries Near sentinel

Cite this Entry

“Sentinel.” Dictionary, Merriam-Webster, Accessed 5 Mar. 2024.

Kids Definition


: sentry

Medical Definition


sen·​ti·​nel ˈsent-ᵊn-əl How to pronounce sentinel (audio)
: being an individual or part of a population potentially susceptible to an infection or infestation that is being monitored for the appearance or recurrence of the causative pathogen or parasite

More from Merriam-Webster on sentinel

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