sentry
gb/sˈɛntɹi/ us/sˈɛntɹi/
B2
English
~ 9800
Senses
0 senses
Noun
B2
entity
1
guard stationed to keep watch
A guard, usually a soldier, who stands in one place and watches to keep an area safe.
Usage pattern:
a sentry at [a place]
Common mistake:
Learners often confuse the spelling and pronunciation of "sentry" with "century". "Sentry" (/ˈsen.tri/) means a guard. "Century" (/ˈsen.tʃər.i/) means 100 years. They are not related in meaning.
Synonyms
guard (Most general word; can be any person protecting a place or person, not just a soldier on a fixed post.)
|
sentinel (Slightly more literary; often interchangeable with "sentry" for a watchful guard, especially in writing.)
|
lookout (Focuses on watching for danger, often from a high place; not necessarily a uniformed or official guard.)
|
watchman (Traditional term for someone guarding a building or area, especially at night; sounds a bit old-fashioned.)
Antonyms
intruder (A person who enters a place without permission, which a sentry is supposed to prevent.)
|
attacker (Someone who tries to harm or break into a place that the sentry is guarding.)
Collocations
post a sentry
|a lone sentry
|sentry duty
|sentry at the gate
|sentry on patrol
|sentry box
Themes
security
|military
|work
|law
|core_vocabulary
Examples
- A sentry stood at the gate, checking the ID of everyone who entered the base.
- The tired sentry paced back and forth along the wall, listening for any sign of movement in the dark.
- They posted a sentry outside the tent to make sure no one disturbed the injured soldier.
- From his position as a sentry on the tower, he could see the entire valley below.
- The alarm was raised when the sentry spotted a figure moving near the fence.
Learner examples
- A sentry stood at the door of the building.
- The army put a sentry at every gate.
- The sentry watched the road all night.
- A sentry stopped us and asked for our names.
Noun
technical
C1
entity
2
security device that watches
A machine or system, like a camera or sensor, that watches a place to keep it safe, like a guard.
Usage pattern:
an electronic sentry at [a place]
Synonyms
security system (Broad term for all equipment and software used to protect a place; may include several "sentries" such as sensors and cameras.)
|
sensor (Focuses on the technical part that detects movement or changes; not all sensors function as guards.)
|
monitoring device (Stresses the act of watching or checking; more formal and technical than "sentry".)
Antonyms
vulnerability (A weak or unprotected point in a system, which an effective sentry is meant to reduce or remove.)
|
blind spot (An area not covered or watched by a sentry or security device.)
Collocations
electronic sentry
|digital sentry
|AI sentry system
|automated sentry
|robotic sentry
Themes
technology
|security
|law
|work
Examples
- The company installed an electronic sentry at the back entrance to detect any movement after hours.
- An AI-powered sentry now monitors the perimeter fence and sends alerts to the control room.
- The robotic sentry turned its cameras toward the sound and began recording automatically.
- Each doorway is protected by a digital sentry that logs everyone who passes through.
- They placed a thermal sentry on the roof to watch for intruders at night.
Learner examples
- A camera sentry watches the door all night.
- The company uses an electronic sentry to protect the car park.
- An AI sentry sends a message if it sees a problem.
- This small device is a sentry for the front gate.
Grammar
Dictionary form
sentry
IPA
GB/sˈɛntɹi/
US/sˈɛntɹi/
Syllables & stress
sen - try (2 syllables)
Stress on 1st syllable (sen)
Word forms
Noun
- Base: sentry
- Plural: sentries
Word family
Forms
sentries
noun
Related words
sentinel
noun C1
Expressions
on sentry duty
1/ˈɔn sˈɛntɹi dˈuti/
fixed phrase
assigned to guard as a sentry
Having the job at that time to be a sentry and watch a place.
Examples
- He was on sentry duty at the north gate when the attack began.
- No one wanted to be on sentry duty in the freezing rain.
- She fell asleep while on sentry duty and was punished the next day.
post a sentry
1/pˈoʊst ə sˈɛntɹi/
fixed phrase
assign a guard as a sentry
To place a guard in a position so they can watch and protect a place.
Examples
- They decided to post a sentry outside the warehouse after the break-in.
- The commander posted a sentry at every entrance to the camp.
- We should post a sentry by the door while the meeting is in progress.
sentry box
1/sˈɛntɹi bˈɑks/
fixed phrase
small shelter for a sentry
A small, usually narrow shelter where a sentry stands to stay dry and protected while on duty.
Examples
- The guard stood in the sentry box to escape the rain.
- Each gate was marked by a painted wooden sentry box.
- Tourists took photos of the soldier in the sentry box outside the palace.
sentry duty
1/sˈɛntɹi dˈuti/
fixed phrase
period of work as a sentry
The job or period of time when someone is a sentry and must watch a place.
Examples
- New recruits are often given sentry duty at night.
- He wrote letters to his family while waiting between rounds of sentry duty.
- They shared the sentry duty so that no one became too tired.
stand sentry
1/stˈænd sˈɛntɹi/
fixed phrase
stand guard as a sentry
To stand in one place and watch it to keep it safe, like a guard.
Examples
- Two soldiers were ordered to stand sentry outside the general's tent.
- She stood sentry at the door while the others searched the room.
- A single officer stood sentry at the main gate throughout the night.