sen·​ti·​nel | \ˈsent-nəl, 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

Some of them snapped selfies with stone-faced police who stood like sentinels, clad in heavy riot gear. Stacy Meichtry, WSJ, "Riots Resurface Across France, Piling Pressure on Macron," 9 Dec. 2018 Inside, an obelisk-like stalagmite stood sentinel atop a mound decked with moss and neon-green ferns. Patrick Scott, WSJ, "A Blow-Your-Mind Adventure in Vietnam’s Caves," 13 Nov. 2018 Torre Truglia This 17th-century tower stands out like a strange, geometric sentinel atop a hill overlooking the Tyrrhenian Sea. Laura Itzkowitz, Condé Nast Traveler, "5 Best Day Trips from Rome," 5 Mar. 2018 But some of the wrecks are already beginning to collapse and the fear is those mussels may one day reduce these silent sentinels to monuments no longer recognizable. CBS News, "Divers race to find Great Lakes shipwrecks threatened by invasive species," 10 July 2018 Pine plantations stand sentinel along two-lane roads where cows graze next to one-room churches. Chelsey Lewis, Milwaukee Journal Sentinel, "Wisconsin's highest point - Timm's Hill - is a quiet escape away from everything," 5 July 2018 Elegant geometrical symmetries abound in its places of worship, and the ancient technique of khachkar—the carving of ornate crosses into steles—is on display outside, where several of the tall stone slabs watch over the complex like holy sentinels. Ryan P. Smith, Smithsonian, "This Free Virtual Reality App Drops Users in the Heart of Historic Armenia," 28 June 2018 The department is in the process of training guardians and sentinels for the upcoming school year. Michael Williams,, "Backpacks banned at Polk schools during last week of class, district says," 21 May 2018 It is introduced by the showstopper: a slightly larger than life-size sentinel that guarded Tut’s Ka, or life force. Christopher Knight,, "How good is the King Tut exhibition? An art critic weighs in," 29 Mar. 2018

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

15 Dec 2018

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 \

Kids Definition of sentinel

: sentry


sen·​ti·​nel | \ˈsent-ᵊn-əl \

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

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