The Collaborative International Dictionary of English v.0.48:
Loathsome \Loath"some\, a. Fitted to cause loathing; exciting disgust; disgusting; as, a loathsome disease. [1913 Webster] The most loathsome and deadly forms of infection. --Macaulay. -- Loath"some*ly. adv. -- Loath"some*ness, n. [1913 Webster]