loathsome in WordNet English dictionary

1. highly offensive; arousing aversion or disgust
   "a disgusting smell"; "distasteful language"; "a loathsome disease"; "the idea of eating meat is repellent to me"; "revolting food"; "a wicked stench"
   disgusting  disgustful  distasteful  foul  loathly  loathsome  repellent  repellant  repelling  revolting  skanky  wicked  yucky 
   
2. causing or able to cause nausea
   "a nauseating smell"; "nauseous offal"; "a sickening stench"
   nauseating  nauseous  noisome  queasy  loathsome  offensive  sickening  vile