Acrimony

Acrimony: harsh, or biting sharpness; bitterness, ill will; severity

 From Latin acer, acris (bitter, pungent, sharp, sour) and the suffix monium (state, or condition).  Acrimony, then, is the “condition of being sour.”

Example: In his official letters he expressed, with great acrimony, his contempt for the king’s character. – Macaulay.