hermetic (adjective)

1. In Greek mythology, Zeus sealed the Titans in a hermetic prison deep beneath the earth.

2. Why did the grape go to the dentist? Because it heard it needed a hermetic seal!

3. Their love was like a hermetic lock, keeping them completely sealed away from the outside world.

4. The haunted house had a hermetic atmosphere, as if it were cut off from the rest of the world.