sentinel

[sen-tn-l]

See more synonyms for sentinel on Thesaurus.com

noun

a person or thing that watches or stands as if watching.
a soldier stationed as a guard to challenge all comers and prevent a surprise attack: to stand sentinel.
Digital Technology. tag¹(def 9a).

verb (used with object), sen·ti·neled, sen·ti·nel·ing or (especially British) sen·ti·nelled, sen·ti·nel·ling.

to watch over or guard as a sentinel.

Origin of sentinel

1570–80; < Middle French sentinelle < Italian sentinella, derivative of Old Italian sentina vigilance (Latin sent(īre) to observe) + -īna -ine²)

Related formssen·ti·nel·like, adjectivesen·ti·nel·ship, nounun·sen·ti·neled, adjectiveun·sen·ti·nelled, adjective

Synonyms for sentinel

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1, 2. sentry, guard, watch, lookout.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for sentinel

lookout, keeper, guard, protector, picket

Examples from the Web for sentinel

Contemporary Examples of sentinel

A web promotion for X-Men: Days of Future Past indicated that the character had been killed by a Sentinel in 2011.
X-Men’s Post-Credits Apocalypse Scene Explained
Rich Goldstein
May 26, 2014
That might have been what happened to the Sentinel that landed in Iran.
Aerial Drones May Be Vulnerable to Sabotage Because of GPS
Tara McKelvey
December 17, 2011
They may be taking some action in the future, given the weaknesses that appear to have been exposed in the Sentinel.
Aerial Drones May Be Vulnerable to Sabotage Because of GPS
Tara McKelvey
December 17, 2011
When Johnston talks about the failure of the Sentinel in Iran, he sounds frustrated.
Aerial Drones May Be Vulnerable to Sabotage Because of GPS
Tara McKelvey
December 17, 2011
A sentinel is present 24 hours a day, seven days a week, 365 days a year, including holidays.
Washington Institution Defies Hurricane
Laura Colarusso
August 26, 2011

Historical Examples of sentinel

Like a sentinel on that solitary plain it overwhelms me with a sense of mystery.
Ballads of a Bohemian
Robert W. Service
After that, we were allowed to come on deck singly, only, and then under a sentinel's charge.
Ned Myers
James Fenimore Cooper
Neither of the lads so much as glanced at the sentinel as they strolled past him.
The Cruise of the Dry Dock
T. S. Stribling
He did not care, now, if he were halted by a British picket or sentinel.
The Dare Boys of 1776
Stephen Angus Cox
This would be difficult, for the reason that there was a sentinel on the deck.
The Dare Boys of 1776
Stephen Angus Cox

British Dictionary definitions for sentinel

sentinel

noun

a person, such as a sentry, assigned to keep guard
computing a character used to indicate the beginning or end of a particular block of information

verb -nels, -nelling or -nelled (tr)

to guard as a sentinel
to post as a sentinel
to provide with a sentinel

Word Origin for sentinel

C16: from Old French sentinelle, from Old Italian sentinella, from sentina watchfulness, from sentire to notice, from Latin

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for sentinel

1570s, from Middle French sentinelle (16c.), from Italian sentinella "a sentinel." OED says "No convincing etymology of the It. word has been proposed," but perhaps (via a notion of "perceive, watch"), from sentire "to hear," from Latin sentire "feel, perceive by the senses" (see sense (n.)).