sentinel

1 of 2

noun

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

sentinel

2 of 2

verb

sentineled or sentinelled; sentineling or sentinelling

transitive verb

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

Examples of sentinel in a Sentence

Noun a lone sentinel kept watch over the fort
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.
Noun
The sentinels of conventional wisdom settled on the view that the Iraq invasion was one of the great own goals of American foreign policy, and that its beneficiary was Iran. Graeme Wood, The Atlantic, 2 Sep. 2025 At the summit, the ruins of the Castle of Monsanto perch atop the craggy heights like a stone sentinel—offering sweeping views over the Beira Baixa plains. Lewis Nunn, Forbes.com, 24 Aug. 2025
Verb
The journey unfolds through fairways framed by stone walls, with an ancient tower standing sentinel behind the 3rd green, before building toward the 8th—another cape hole bending back along the coast in the opposite direction of the 2nd. Jeff Goudy, Forbes.com, 28 Aug. 2025 Since the outbreak was first reported in a Texas dairy herd last March, dead barn cats have served as sentinel warnings to veterinarians and investigators of the virus’ presence on a farm. Susanne Rust, Los Angeles Times, 18 Jan. 2025 See All Example Sentences for sentinel

Word History

Etymology

Noun

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

First Known Use

Noun

1579, in the meaning defined above

Verb

1593, in the meaning defined at sense 1

Time Traveler
The first known use of sentinel was in 1579

Browse Nearby Words

Cite this Entry

“Sentinel.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sentinel. Accessed 9 Sep. 2025.

Kids Definition

sentinel

noun
sen·​ti·​nel
ˈsent-(ə-)nəl
: sentry

Medical Definition

sentinel

adjective
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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