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sentinel

[ sen-tn-l ]
/ ˈsɛn tn l /
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See synonyms for: sentinel / sentineled / sentineling / sentinelled 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.
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Origin of sentinel

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

OTHER WORDS FROM sentinel

sen·ti·nel·like, adjectivesen·ti·nel·ship, nounun·sen·ti·neled, adjectiveun·sen·ti·nelled, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use sentinel in a sentence

British Dictionary definitions for sentinel

sentinel
/ (ˈsɛntɪnəl) /

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
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