See lull in Webster's New World Roget's A-Z Thesaurus II
verb
To make or become calm:
allay, balm, becalm, calm (down), quiet, settle, still, tranquilize. See calm
noun
An absence of motion or disturbance:
calm, calmness, hush, peace, peacefulness, placidity, placidness, quiet, quietness, serenity, stillness, tranquillity, untroubledness. See calm
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