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1. Fall slowly to a stable position, usually on a surface or the ground
   "dust settled down on the roofs"
   - settle
    
2. Become settled or established and stable in one's residence or life style
   "He finally settled down"
   - settle, root, take root, steady down
    
3. Become quiet or calm, especially after a state of agitation
   "It took a while after the baby was born for things to settle down again."
   - calm, calm down, cool off, chill out, simmer down, cool it, wind down, take a chill pill

Derived forms: settles down, settled down, settling down

Type of: change state, lay, place, pose, position, put, set, stabilise [Brit], stabilize, turn