sentry

noun

sen·​try ˈsen-trē 

plural sentries

: guard, watch

especially : a soldier standing guard at a point of passage (such as a gate)

Synonyms of sentry

• guard
• guardian
• custodian
• warden
• sentinel
• keeper

Examples of sentry in a Sentence

The general placed an armed sentry at the bridge.

a sentry posted to watch for intruders

Recent Examples on the Web

The robot is also designed to perform sentry duties, including identifying personnel and issuing alerts when abnormal situations are detected. — Maria Mocerino, Interesting Engineering, 22 Aug. 2026

In humans, traits such as neuroticism and recklessness appear to have some evolutionary basis—emerging perhaps to provide our species with sentries who alerted us to threats, and with explorers who led the way to new food sources. — Vann R. Newkirk Ii, The Atlantic, 28 July 2026

From Newt's family making first contact with a Facehugger to a wonderfully tense sentry gun sequence, Cameron's extra footage enhances a classic. — Richard Edwards, Space.com, 17 July 2026

The former is heralded with a blast of horns; the latter guards its inner sanctum behind Tobie Windham’s officious sentry. — Amy Nicholson, Los Angeles Times, 8 July 2026

Word History

Etymology

perhaps from obsolete sentry sanctuary, watchtower

First Known Use

1608, in the meaning defined above

Phrases Containing sentry

• sentry box
• stand sentry

Rhymes for sentry

• entry
• gentry
• complementary
• elementary

Kids Definition

sentry

noun

sen·​try ˈsen-trē 

plural sentries

: guard entry 1 sense 3a

especially : a soldier standing guard at a point of passage