Scuba (noun)

A device that allows a person to breathe underwater, consisting of a tank of compressed air and a regulator to control the flow of air.

Origin:

Acronym of self-contained underwater breathing apparatus.

Examples:

1. He went scuba diving to explore the coral reef.
2. I am going to take a scuba diving lesson next weekend.
3. The scuba gear allowed him to stay underwater for an hour.
4. She rented a scuba diving equipment for the day.
5. The scuba diving instructor showed them how to use the equipment properly.