upheaval
n. C / U C1 Advanced US //əpˈhivəɫ// UK //ʌphˈiːvəl// up·heaval
n. a big, sudden change that causes a lot of trouble or confusion. It often happens in a society, a government, or someone's personal life.
n. a violent or sudden change or disruption to something. Often refers to social, political, or personal instability.
The sudden move caused a lot of upheaval in the family.
The country experienced massive political upheaval after the unexpected results of the national election.
Economic historians often point to the industrial revolution as a period of unprecedented social upheaval that permanently altered the relationship between labor and capital.
From upheave + -al.
Usage
Both uncountable for the general state of chaos and countable when referring to a specific event.