Sentence:  After Mr. Rowland spoke, his wife, Patricia, delivered a spoof on the poem "Twas the Night Before Christmas," that was a stinging sing-song rebuke of the news organizations that had reported on her husband's shortcomings and the widening federal investigation into his administration. Referring to the news media, she said: "They used to be good girls and boys, Santa said. But the <WSD>poison pen's</WSD> power has gone to their head." 
Meaning of the word marked with <WSD> tags:  A manner, means, or tone of expression had by a written work, characterized by spitefulness, defamation, and/or intimidation directed toward a person, organization, or point of view.