scathing

Etymology

verb

1. present participle and gerund of scathe

adj

1. Harshly or bitterly critical; vitriolic.
   For months, Dati warned she would refuse to stand aside. Now she has stunned the political class with an open letter to Fillon in Le Monde, a scathing character assassination accusing him of the "lone ambition" of a disillusioned political elite, of doing politics in a way that "never favoured women" and stopping ethnic-minority candidates from progressing at elections. She said he was committing "a sad mistake" in trying to run in Paris. December 14, 2011, Angelique Chrisafis, “Rachida Dati accuses French PM of sexism and elitism”, in Guardian
2. Harmful or painful; acerbic.