[ sen-tn-l ]
/ ˈsɛn tn l /


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 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for sentinel

British Dictionary definitions for sentinel


/ (ˈsɛntɪnəl) /


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.)).

Online Etymology Dictionary, © 2010 Douglas Harper