All 3 Uses

Caspian Sea
in
The Hunt for Red October
(Auto-generated)

Thirty-two meters long and diesel-electric powered, it was based in the Caspian Sea, far from the eyes of imperialist spies, and kept in a covered dock, hidden from their photographic satellites.†
Chpt 2.
After a week of following the model around the north end of the Caspian Sea in an electrically powered launch, trailing the best passive sonar array his country had yet made, he thought he had found a flaw.†
Chpt 2.
He had helped with the designing of her revolutionary drive system and had inspected the model, which had been running on the Caspian Sea for some years in absolute secrecy.†
Chpt 3. *

Definitions:

(1) (Caspian Sea)
a large saltwater lake between Iran and Russia fed by the Volga River; the largest inland body of water in the world
(2) (meaning too rare to warrant focus)