| malignant(adjective, diseased, spreading) |
| destructive(adjective, injurious, devastating, malignant, destroying) |
| baneful(adjective, harmful, injurious, damaging, deadly) |
| evil(adjective, harmful, injurious, damaging, deadly) |
| harmful(adjective, injurious, damaging, deadly, fatal) |
| mortal(adjective, harmful, injurious, damaging, deadly) |
| virulent |
| calamitous(adjective, harmful, injurious, damaging, deadly) |
| cankerous(adjective, pernicious) |
| carcinogenic(adjective, malignant) |
| carcinomatous(adjective, malignant) |
| malign |
| fatal(adjective, harmful, injurious, damaging, deadly) |
| hurtful(adjective, harmful, injurious, damaging, deadly) |
| ill(adjective, baneful) |
| injurious(adjective, harmful, damaging, deadly, fatal) |
| noxious(adjective, harmful, injurious, damaging, deadly) |
| pestilent |
| poisonous(adjective, baneful) |
| ruinous(adjective, harmful, injurious, damaging, deadly) |