(of a body of water) Completely still with no waves and no wind.

(nautical) The condition of a perfectly flat sea with no waves and no wind.

simple past tense and past participle of calm down

present participle of calm down

(simile, of water) Very calm, not choppy.

(idiomatic) Extremely calm

(idiomatic) Extreme calm, utter calmness

plural of calm wind

(nautical) The condition of a perfectly flat sea with no waves and no wind.

(simile) Synonym of cool as a cucumber