Which nautical term defines a tranquil weather without wind?

Sea like a mirror we call "slick cam"

There is an area in the Atlantic near the equator called the 'doldrums ' which trapped sailing ships in calm water sometimes for weeks. The whaling ships used their whale hunting boats to tow the mother ship to an area of breeze but most passenger/cargo ships just had to sit it out resulting in water and food rationing.

I play this game when I am in the doldrums.

Ruby, no !