Alternative form of poison-pen letter

(idiomatic) A missive which is malicious, insulting, and/or defamatory toward a person, organization, or point of view, especially one which is unsigned.

plural of poison pen

plural of poisonmonger

One who peddles poison (literally or figuratively).

Capable of being poisoned. / (obsolete) poisonous

(medicine) A disease occasioned or aggravated by overcrowding, especially due to lack of ventilation.

plural of crowd-poisoning

plural of poison pill

(obsolete) poisonous