Synonyms and related words :
bitter, disagreeable, dislikable, displeasing, distasteful, sour, thankless, ugly, unalluring, unamusing, unappealing, unappetizing, unattractive, undelectable, undelicious, undesirable, unengaging, unentertaining, uneventful, unexciting, unfunny, uninteresting, uninviting, unlikable, unpalatable, unpleasant, unpleasing, unsavory, untasteful, unwelcome, unwitty