Stillness, quiet, tranquillity, serenity; freedom from agitation or disturbance. literal of the weather, air, or sea: opposed to storm; = calmness, n.…

The state or quality of being calm; stillness, tranquillity, quietness. Stillness of the sea or other surface of water, of the atmosphere, or…

(with reference to a body of water) complete stillness, such that the surface of the water resembles a mirror.

a calm when the sea is smooth as glass.