| Deleterious (a.) Hurtful; noxious; destructive; pernicious; as, a deleterious plant or quality; a deleterious example. Thesaurus Entries baleful, baneful, corroding, corrosive, corrupting, corruptive, counterproductive, damaging, deadly, destroying, destructive, detrimental, disadvantageous, disserviceable, distressing, harmful, hurtful, injurious, lethal, malefic, malevolent, malign, malignant, mischievous, noisome, noxious, ominous, pernicious, poisonous, prejudicial, ruining, ruinous, scatheful, toxic, unadvantageous, unfavorable, unprofitable, unrewarding, useless, venenate, veneniferous, venenous, venomous, vicious, virulent, worthless |