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

Definition of sentinel

 (Entry 1 of 2)

: sentry


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


a lone sentinel kept watch over the fort

Recent Examples on the Web: Noun

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 On a tower in the Brazilian rain forest, a sentinel scans the horizon for the first signs of fire. Brian K. Sullivan, Fortune, "How Artificial Intelligence Could Help Fight Climate Change-Driven Wildfires and Save Lives," 10 Aug. 2019 Some sites have views spanning all four of this area’s sentinel landmarks: Longs Peak, Mt. Evans, Devil’s Head and Pikes Peak. Mark Samuelson, The Denver Post, "Come see a custom farmhouse ranch on 1.6 acres at Fox Hill, where fruit is already on the trees and fresh eggs are waiting," 18 July 2019 In the distance, the towering rocks of Zion National Park stood like sentinels. James Murren,, "At Utah's Gooseberry Mesa, the joy and power of wilderness prevail," 13 July 2019 Six garbage cans overflowing with plastic bags, loose pieces of clothing and paper waste line the McMicken curb like sentinels. Mark Curnutte,, "4 addresses in 4 months: This is what poverty looks like for this Cincinnati family," 10 July 2019 From that vantage point, the Hallgrímskirkja feels like a sentinel quietly watching over Reykjavík. Rumela Basu, National Geographic, "Iceland’s tallest church was inspired by volcanoes," 27 June 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

8 Sep 2019

Look-up Popularity

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

: sentry


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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More from Merriam-Webster on sentinel

Thesaurus: All synonyms and antonyms for sentinel

Spanish Central: Translation of sentinel

Nglish: Translation of sentinel for Spanish Speakers

Britannica English: Translation of sentinel for Arabic Speakers

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).


to make a temporary encampment

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