Loathsome, a.
Fitted to cause loathing; exciting disgust; disgusting. The most loathsome and deadly forms of infection. Macaulay. -- Loath"some*ly. adv. -- Loath"some*ness, n.
Shades of meaning
Fernald lists loathsome only as an antonym, under delicious.
He lists it without comment; the entries above explain its neighbors.
Synonyms
none given