fog in WordNet English dictionary

1. make less visible or unclear
   "The stars are obscured by the clouds"; "the big elm tree obscures our view of the valley"
   obscure  befog  becloud  obnubilate  haze over  fog  cloud  mist 
   

1. confusion characterized by lack of clarity
   daze  fog  haze 
   
2. droplets of water vapor suspended in the air near the ground
   fog 
   
3. an atmosphere in which visibility is reduced because of a cloud of some substance
   fog  fogginess  murk  murkiness