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

• 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

Effectively the solar cell allows the drone to act as a CCTV sentry during daylight hours, saving battery power for when a target is spotted. —David Hambling, Forbes.com, 2 July 2025

The tree had long been a way marker and memory maker: a site of wedding proposals and remembrance ceremonies, a sentry in photos from one-in-a-lifetime family vacations, taped to fridges across the world. —Amelia Nierenberg, New York Times, 29 Apr. 2025

Anduril makes everything from small drones to sentry towers used to police the U.S.-Mexico border systems to enable pilotless vehicles. —William Hartung, Forbes, 26 Dec. 2024

Occasionally, gang members would come rushing in and that’s when auto sentry guns would be useful. —Gieson Cacho, Mercury News, 1 Apr. 2025

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