sentinel

S1E1N1T1I1N1E1L1
/ˈsɛn.tɪ.nəl/

noun

A sentry, watch, or guard.

“The <xmp> tag is a sentinel that suspends web-page processing and displays the subsequent text literally”

CommonScrabble 8

Meanings

sentinel1

nounsentinel (plural sentinels)

plural sentinels · alternative obsolete centinel

  1. A sentry, watch, or guard.

    that princes do keep due sentinel

    1625, Francis [Bacon], “Of Empire”, in The Essayes […], 3rd edition, London: […] Iohn Haviland for Hanna Barret, →OCLC
    2 more examples

    They promised faithfully to bear their confinement with patience, and were very thankful that they had such good usage as to have provisions and light left them; for Friday gave them candles (such as we made ourselves) for their comfort; and they did not know but that he stood sentinel over them at the entrance.

    1719 May 6 (Gregorian calendar), [Daniel Defoe], The Life and Strange Surprizing Adventures of Robinson Crusoe, […], London: […] W[illiam] Taylor […], →OCLC

    the sentinels who paced the ramparts

    1849–1861, Thomas Babington Macaulay, chapter XII, in The History of England from the Accession of James the Second, volume (please specify |volume=I to V), London: Longman, Brown, Green, and Longmans, →OCLC
  2. obsoleteA private soldier.

    “I will not permit the poorest centinel to be treated with injustice.”

    1789, John Moore, Zeluco, Valancourt, published 2008, page 33
  3. computerA unique value recognised by a computer program for processing in a special way, or marking the end of a set of data.

    The <xmp> tag is a sentinel that suspends web-page processing and displays the subsequent text literally

    1 more example

    […] a sentinel value that indicates a missing entry.

    2016, Jake VanderPlas, Python Data Science Handbook, page 120
  4. attributiveepidemiologyA sign of a health risk (e.g. a disease, an adverse effect).

    Sentinel animals can be used to explore endemic diseases.

verbsentinel (third-person singular simple present sentinels, present participle (US) sentineling or (UK) sentinelling, simple past and past participle (US) sentineled or (UK) sentinelled)

present singular third person sentinels · US participle present sentineling · UK participle present sentinelling · US participle past sentineled · US past sentineled · UK participle past sentinelled · UK past sentinelled · alternative obsolete centinel

  1. transitiveTo watch over as a guard.

    He sentineled the north wall.

  2. transitiveTo post a guard for.

    He sentineled the north wall with just one man.

    1 more example

    The old-fashioned stoop, with its suggestive benches on either side, lay solitary and silent in the moonlight; the garden path, weedily overgrown since father's death, and sentineled here and there with ragged hollyhock, lay quiet and dew-laden […]

    1873, Harper's New Monthly Magazine, volume 46, page 562

Sentinel2

Synonyms & antonyms

nouna person employed to keep watch for some anticipated event

Synonym sets from Open English WordNet, CC BY 4.0.

Origin

  1. Old Italiansentinella
  2. Middle Frenchsentinelle“watch or guard kept by a soldier”
  3. Englishsentinel

First attested in the 1570s from Middle French sentinelle (“watch or guard kept by a soldier”), from Old Italian sentinella, probably from sentina + -ella, from sentire (“perceive, watch, hear”), from sentiō (“feel, perceive by the senses”). See also sense, sentient.

Full word history & related roots →

Translations

Arabic حَارِس, خَفِير
  • حَارِس (ḥāris)a sentry or guard
  • خَفِير (ḵafīr)a sentry or guard
  • غَفِير (ḡafīr)a sentry or guard
Bulgarian страж, часови́
  • страж (straž)a sentry or guard
  • часови́ (časoví)a sentry or guard
  • часово́й (časovój)a sentry or guard
  • охранявам (ohranjavam)To watch over something as a guard
Catalan sentinella
  • sentinellaa sentry or guard
Chinese Mandarin 哨兵, 步哨
  • 哨兵 (shàobīng)a sentry or guard
  • 步哨 (bùshào)a sentry or guard
Czech hlídka, stráž
  • hlídkaa sentry or guard
  • stráža sentry or guard
Danish skildvagt, vagtpost
  • skildvagta sentry or guard
  • vagtposta sentry or guard
  • stå vagtTo watch over something as a guard
Dutch wacht
  • wachta sentry or guard
Finnish vartija, vahti
  • vartijaa sentry or guard
  • vahtia sentry or guard
  • vahtia unique phrase of characters
  • vahtiaTo watch over something as a guard
  • vartioidaTo watch over something as a guard
French factionnaire, sentinelle
  • factionnairea sentry or guard
  • sentinellea sentry or guard
  • regarderTo watch over something as a guard
German Wache, Wachposten
  • Wachea sentry or guard
  • Wachpostena sentry or guard
  • Wächtera sentry or guard
  • Wächterina sentry or guard
  • Markierunga unique phrase of characters
  • Schlüsselworta unique phrase of characters
  • bewachenTo watch over something as a guard
Greek σκοπός, φρουρός
  • σκοπός (skopós)a sentry or guard
  • φρουρός (frourós)a sentry or guard
Hindi प्रहरी
  • प्रहरी (prahrī)a sentry or guard
Hungarian őrszem
  • őrszema sentry or guard
Irish fairtheoir, fairtheoir
  • fairtheoira sentry or guard
  • fairtheoira unique phrase of characters
Italian sentinella
  • sentinellaa sentry or guard
Japanese 歩哨, 番兵
  • 歩哨 (hoshō)a sentry or guard
  • 番兵 (banpei)a sentry or guard
Korean 초병, 보초병
  • 초병 (chobyeong)a sentry or guard
  • 보초병 (bochobyeong)a sentry or guard
  • 감시병 (gamsibyeong)a sentry or guard
Latin vigil, custos
  • vigila sentry or guard
  • custosa sentry or guard
  • excubitora sentry or guard
  • praesesa sentry or guard
Polish wartownik, strażnik
  • wartownika sentry or guard
  • strażnika sentry or guard
Portuguese sentinela, vigia
  • sentinelaa sentry or guard
  • vigiaa sentry or guard
  • vigiarTo watch over something as a guard
Russian часово́й, карау́льный
  • часово́й (časovój)a sentry or guard
  • карау́льный (karaúlʹnyj)a sentry or guard
  • охра́нник (oxránnik)a sentry or guard
  • страж (straž)a sentry or guard
Scottish Gaelic freiceadan
  • freiceadana sentry or guard
Slovak hliadka, stráž
  • hliadkaa sentry or guard
  • stráža sentry or guard
Spanish centinela
  • centinelaa sentry or guard
Swedish vaktpost, skyltvakt
  • vaktposta sentry or guard
  • skyltvakta sentry or guard
Turkish gözcü, koruyucu
  • gözcüa sentry or guard
  • koruyucua sentry or guard
  • nöbetçia sentry or guard
  • sembola unique phrase of characters
  • simgea unique phrase of characters
Ukrainian вартови́й, охороняти
  • вартови́й (vartovýj)a sentry or guard
  • охороняти (oxoronjaty)To watch over something as a guard
Welsh gwarchodwr, gwyliwr
  • gwarchodwra sentry or guard
  • gwyliwra sentry or guard
Cite this entry
APA

sentinel. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/sentinel

MLA

“sentinel.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/sentinel. Accessed November 2, 2026.

Chicago

WatkinsX Dictionary, s.v. “sentinel,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/sentinel.

Source: sentinel on Wiktionary, CC BY-SA 4.0.