This is another word I am fond of, but I’m not entirely sure why.
The root word here is ‘heave’ which means to lift or pull something heavy and implies considerable effort. So, the movement may be upwards or simply at the same level.
The workmen heaved the last of the beams up to the second floor.
But we also use it to make a sound in conjunction with our breathing.
Ellie heaved a sigh of relief when she saw her cat was safe and sound.
For the scatologically minded heave up means to vomit.
Juan started heaving up overboard once the yacht struck rolling seas.
Heave in geology means a sideways movement or shift in the earth. So, not surprisingly, upheaval (the verb form upheave doesn’t exist) can refer to the shifting up of land in an earthquake.
The quake caused noticeable upheavals in marshlands creating small new islands.
The most common use though is to describe a disturbance, change or disruption to something in society.
There has been a major upheaval in the airline industry with the merger of the top two airlines and the declared bankruptcy of the third.
The US underwent a number of social upheavals in the 60s and 70s with the Civil Rights movement and the hippies.