Acrimony
Harsh or biting sharpness of language or fealings - Acrimonious, acrimoniously, acrimoniousness.
Your acrimony has caused many a harsh situation in the classroom.
acrimonious
stinging, bitter in temper or tone
An acrimonious debate between the two candidates.
Acrimonial
A negative endorsement of a product, person, service , brand etc
the opposite of testimonial.
the opposite of testimonial.
after a poor experience at a restaurant people often send out a stinging acrimonial using Twitter.