Synonyms of poisonous

1 Syllable

bad

2 Syllables

deadliest, fatal, deadlier, septic, hard-time, toxic, noxious, evil, lethal, corrupt, morbid, nocuous, vicious, nocent, poison, deadly, mortal, peccant, hurtful

3 Syllables

pernicious, death-dealing, baleful, viperous, mephitic, injurious, necrotic, malicious, toxicant, venomous, blackhearted, dangerous, contagious, unpleasant, baneful, noisome, sinister, miasmatic, virulent, malignant

4 Syllables

inedible, malodorous, insalubrious, impartible, pestiferous, pestilential, transmissible, detrimental, deleterious, unnutritious, corruptive, toxiferous, uneatable, destructive, infective

5 Syllables

inoculable, unconducive, unpleasant-tasting, unwholesome, indigestible, insalutary