Simple Definition of sentry
: a soldier who guards a door, gate, etc.
Examples of sentry in a sentence
The general placed an armed sentry at the bridge.
<a sentry posted to watch for intruders>
Origin of sentry
perhaps from obsolete sentry sanctuary, watchtower
First Known Use: 1608
SENTRY Defined for Kids
Definition of sentry for Students
: a person (as a soldier) on duty as a guard
Seen and Heard
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