cushion in WordNet English dictionary

1. protect from impact
   "cushion the blow"
   cushion  buffer  soften 
   

1. a soft bag filled with air or a mass of padding such as feathers or foam rubber etc.
   cushion 
   
2. a mechanical damper; absorbs energy of sudden impulses
   "the old car needed a new set of shocks"
   shock absorber  shock  cushion 
   
3. the layer of air that supports a hovercraft or similar vehicle
   cushion