WordNet sense 1 (causing or able to cause nausea):

nauseating, nauseous, noisome, queasy, sickening, vile

WordNet sense 2 (violating or tending to violate or offend against):

violative

WordNet sense 3 (offending against or breaking a law or rule):

offending

WordNet sense 4 (involving invasion or aggressive attack):

invading

WordNet sense 5 (causing disapproval or protest):

obnoxious

WordNet sense 6 (grossly offensive to decency or morality; causing horror):

hideous, horrid, outrageous

WordNet sense 7 (highly offensive; arousing aversion or disgust):

disgusting, distasteful, foul, loathsome, repellent, revolting, wicked, yucky, disgustful, loathly, repellant, repelling, skanky, wicked

WordNet sense 8 (gruesomely indicative of death or the dead):

ghastly

WordNet sense 9 (offensive to the mind):

abhorrent, detestable, repugnant, repulsive

WordNet sense 10 (disposed to attack):

attacking

WordNet sense 11 (expressing offensive reproach):

abusive, insulting, opprobrious, scurrilous

WordNet sense 12 (morally offensive):

unsavory, unsavoury

WordNet sense 13 (the action of attacking an enemy):

offense, offence, offense

WordNet sense 14 (of an offensive substitute for inoffensive terminology):

dysphemistic