Acrimonious

caustic, stinging, or bitter in nature, speech, behavior, etc.:
an acrimonious answer; an acrimonious dispute.
Contemporary Examples

That ability to straddle two sides of an acrimonious divide has served Leavell well—not only in politics, but also in music.
Stones’ Keyboard Man Is Ardent Forester David A. Graham June 15, 2011

And as our political life grows more divided and acrimonious, so will our legal system.
A Reminder: Our Justices are Politicians in Robes Jedediah Purdy November 12, 2014

“How acrimonious that gets is really up to them,” Issa’s spokesman says of the Democrats.
The GOP’s New Top Cop Howard Kurtz November 26, 2010

But Nemazee left abruptly, according to knowledgeable sources, after he and Schumer had an acrimonious falling out.
The Dems’ Corrupt Money Man Lloyd Grove March 20, 2010

Craig Dershowitz spent $60,000 fighting for the return of his dog Knuckles after an acrimonious breakup with his girlfriend.
Divorce Is Going to the Dogs, Literally Keli Goff June 19, 2014

Historical Examples

The answers which he received from Versailles were cold and acrimonious.
The History of England from the Accession of James II. Thomas Babington Macaulay

Gallagher had written down every word of an acrimonious debate.
General John Regan George A. Birmingham

He was a voluminous writer, and a keen and acrimonious controversialist against the Puritans.
A Short Biographical Dictionary of English Literature John W. Cousin

acrimonious discussion as to the running of the Bleachery Life.
Working With the Working Woman Cornelia Stratton Parker

In these often acrimonious controversies, Sherman himself took a leading part.
Life of Wm. Tecumseh Sherman. W. Fletcher Johnson

adjective
characterized by bitterness or sharpness of manner, speech, temper, etc
adj.

1610s, “acrid,” from French acrimonieux, from Medieval Latin acrimoniosus, from Latin acrimonia (see acrimony). Of dispositions, debates, etc., from 1775. Related: Acrimoniously; acrimoniousness.