POISONPENLETTER
Poison pen letter
A poison pen letter is a letter or note containing unpleasant, abusive or malicious statements or accusations about the recipient or a third party. It is usually sent anonymously. Poison pen letters are usually composed and sent to upset the recipient. They differ from blackmail, which is intended to obtain something, in that they are purely malicious.The above text is a snippet from Wikipedia: Poison pen letter
and as such is available under the Creative Commons Attribution/Share-Alike License.