peephole

She looked through the peephole to see who was knocking on the door.

The hotel room had a small peephole in the door for added security.

He felt uncomfortable knowing that someone could be watching him through the peephole.

The detective used a peephole to observe the suspect's movements without being noticed.

The landlord installed a peephole in the front door for the tenants' safety.

She cautiously peered through the peephole before opening the door to strangers.

The hotel guest used the peephole to check who was outside before opening the door.

The peephole in the door provided a discreet way to see who was outside without opening it.

She accidentally covered the peephole with a sticker, making it difficult to see outside.

The spy used a special device to look through the peephole and gather information.