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Synonyms

sentinel

American  
[sen-tn-l] / ˈsɛn tn l /

noun

  1. a person or thing that watches or stands as if watching.

    The cats were the sentinels of the house, patrolling constantly for rodents, dogs, and other invaders.

    Synonyms:
    lookout, watch, guard, sentry
  2. a soldier stationed as a guard to challenge all comers and prevent a surprise attack.

    Lincoln refused to make his home mansion a garrison during the Civil War, but plain-clothes sentinels did patrol the property

    Synonyms:
    lookout, watch, guard, sentry
  3. Digital Technology. tag.

  4. Medicine/Medical. an indication or mark that a disease is present or prevalent.

    New viruses in the wastewater can be used as sentinels of future outbreaks.


verb (used with object)

sentineled, sentineling, sentinelled, sentinelling
  1. to watch over or guard as a sentinel.

    This monument sentinels each soldier's grave as a shrine.

adjective

  1. Medicine/Medical. relating to or being an indication of a disease's presence or prevalence.

    Pregnant women attending prenatal appointments serve as a sentinel population for the prevalence of malaria in the region.

    The sentinel lymph nodes are the first lymph nodes that the cancer cells reach if they spread.

sentinel British  
/ ˈsɛntɪnəl /

noun

  1. a person, such as a sentry, assigned to keep guard

  2. computing a character used to indicate the beginning or end of a particular block of information

"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

verb

  1. to guard as a sentinel

  2. to post as a sentinel

  3. to provide with a sentinel

"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

Other Word Forms

  • sentinellike adjective
  • sentinelship noun
  • unsentineled adjective
  • unsentinelled adjective

Etymology

Origin of sentinel

First recorded in 1570–80; from Middle French sentinelle, from Italian sentinella, derivative of Old Italian sentina “vigilance,” from Latin sent(īre) “to feel” + -īna -ine 2

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The steely husks stood sentinel over unfathomable loss for weeks or months until they were towed away and sold as scrap.

From Los Angeles Times

"When you only have a handful of species that can persist in environments like that, and they're really sensitive to change, those serve as really good sentinel taxa," Adams said.

From Science Daily

I wanted to ask him if he’d sign this book, which had now begun to write its own mythology as it sat sentinel over his other signed books on the shelf behind me.

From Los Angeles Times

Ahead of our return to the city, we drive back up the ridge, back through Burguete, the inn still shuttered, and up to Roncesvalles, where the old monastery looms like a sentinel over the pass.

From Salon

Climate change is sure to batter this stone sentinel with higher seas and stronger storms.

From Los Angeles Times