sen·​ti·​nel | \ ˈsent-nəl How to pronounce sentinel (audio) , ˈsen-tə-nəl\

Definition of sentinel

 (Entry 1 of 2)


sentineled or sentinelled; sentineling or sentinelling

Definition of sentinel (Entry 2 of 2)

transitive verb

1 : to watch over as a sentinel
2 : to furnish with a sentinel
3 : to post as sentinel

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Examples of sentinel in a Sentence

Noun a lone sentinel kept watch over the fort
Recent Examples on the Web: Noun Stand in the middle and you’ll be buffeted by rich vocal harmony spilling forth in waves from the blank sentinels that surround you. Murray Whyte,, "‘The Forty Part Motet’ strikes a perfect note at the Clark Art Institute," 15 Aug. 2019 Separately, Florida health officials announced in late July that several sentinel chickens in the state tested positive for EEE. Fox News, "Potentially fatal mosquito-borne EEE virus detected in Delaware: state officials," 8 Aug. 2019 Perfection then and again at dawn, as the sun rose behind Zion's sentinels, smearing the morning sky in soft pastels. James Murren,, "At Utah's Gooseberry Mesa, the joy and power of wilderness prevail," 13 July 2019 In a bed like that, with those towering posts standing like sentinels at the corners, a girl would have room to dream. Mary Schmich,, "Column: Nobody wants my mother’s four-poster bed. Should I take it?," 16 Aug. 2019 In Florida and Delaware, the virus has been detected in sentinel chickens, though neither state has seen any cases reported in humans. Scottie Andrew, CNN, "A fourth person in Massachusetts has contracted EEE, the rare but dangerous mosquito-borne virus," 26 Aug. 2019 Testing showed no spread of cancer to Dennis’ blood or sentinel lymph nodes, a first stop for cancer that spreads outside the breast. Meredith Cohn,, "Patient with terminal cancer sues University of Maryland St. Joseph Medical Center over her care," 28 Aug. 2019 The shape-shifting materials could be used to deliver drugs, and to create sentinels for almost any biological signal, researchers report in Science on 22 August1. Ewen Callaway, Scientific American, "Gene Editing Transforms Gel into Shape-Shifting Smart Material," 23 Aug. 2019 Soldiers, farmers, Native Americans, deer and horses (with beer-bottle manes), all silent sentinels of a vanished pioneer life, stared out of stiff stone faces, waiting to be remembered. Robert Simonson, New York Times, "A Road Trip to the Fiberglass Frontier of Northern Wisconsin," 14 Aug. 2019 Recent Examples on the Web: Verb It has been guarded every hour of every day since 1937 by elite Tomb Guard sentinels. Jesse Ryan, USA TODAY, "VR: Witness a sacred ritual and America’s highest honor at Arlington National Cemetery," 29 May 2017 When Chinese leaders gaze out toward the Pacific, their panorama is obstructed by a string of military airfields, naval anchorages, radar emplacements and listening posts sentineled by U.S. forces and their allies. Andrew Browne, WSJ, "To China, America Finally Looks Vulnerable," 14 Mar. 2017

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


1579, in the meaning defined above


1593, in the meaning defined at sense 1

History and Etymology for sentinel


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

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Statistics for sentinel

Last Updated

20 Oct 2019

Time Traveler for sentinel

The first known use of sentinel was in 1579

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More Definitions for sentinel


sen·​ti·​nel | \ ˈsen-tə-nəl How to pronounce sentinel (audio) \

Kids Definition of sentinel


sen·​ti·​nel | \ ˈsent-ᵊn-əl How to pronounce sentinel (audio) \

Medical Definition of sentinel

: 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

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Comments on sentinel

What made you want to look up sentinel? Please tell us where you read or heard it (including the quote, if possible).


not being in agreement or harmony

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