Subside

1. verb

   descend into or as if into some soft substance or place

   “He sank into bed”

   Similar: sink

2. verb

   sink to a lower level or form a depression

   “the valleys subside”

3. verb

   sink down or precipitate

   “the mud subsides when the waters become calm”

   Similar: settle

4. verb

   wear off or die down

   “The pain subsided”

   Similar: lessen