adverse, counter, disadvantageous, hostile, inimical, negative, prejudicial, unfriendly, unsympathetic, untoward

bad, baleful, baneful, evildamaging, deleterious, destructive, detrimental, fatal, harmful, hurtful, ill, injurious, lethal, malignant, murderous, noxious, pernicious, poisonous, ruinous, threatening, troublesome, unhealthy, woundingdangerous, hazardous, imperiling(or imperilling), jeopardizing, parlous, perilous, risky, unsafecalumnious, defamatory, detractive, offensive, scathing, slanderousantagonistic, antipathetic, inhospitable, intolerant, uncongenial, uncooperativecompeting, conflicting, counteracting, countering, opposing, resistant, resisting

advantageous, favorable, friendly, positive, supportive, sympathetic, well-disposed

beneficial, good, helpful, propitious, usefulharmless, innocent, innocuous, inoffensive, nondestructive, nonfatal, nonlethal, nonthreateningunresistanttolerant, understandingaffable, agreeable, amiable, amicable, benign, benignant, complying, congenial, cordial, friendly, hospitable