To fall into a state of quiet; to cease to rage; to be calmed; to settle down; to become tranquil; to abate; as, the sea subsides; the tumults of war will subside; the fever has subsided
If fighting subsides, it becomes less intense or general. Violence has subsided following two days of riots
wear off or die down; "The pain subsided" sink down or precipitate; "the mud subsides when the waters become calm" sink to a lower level or form a depression; "the valleys subside