wan in WordNet English dictionary

1. abnormally deficient in color as suggesting physical or emotional distress
   "the pallid face of the invalid"; "her wan face suddenly flushed"
   pale  pallid  wan 
   
2. (of light) lacking in intensity or brightness; dim or feeble
   "the pale light of a half moon"; "a pale sun"; "the late afternoon light coming through the el tracks fell in pale oblongs on the street"; "a pallid sky"; "the pale (or wan) stars"; "the wan light of dawn"
   pale  pallid  wan  sick 
   
3. lacking vitality as from weariness or illness or unhappiness
   "a wan smile"
   wan 
   

1. become pale and sickly
   wan