the lowest point of something
nadir - bottom
The word ‘nadir’ is most commonly used to describe the lowest point of somebody’s life or career. It implies an extreme state of adversity from which it is impossible to sink any lower. While it typically has negative connotations, it can also be a positive as a nadir may be the starting point of a recovery. Sometimes encountered with the word ‘zenith’, which is its exact opposite.
By the end of the year, the recession had reached its nadir, and the economy slowly began to recover.
Failure to secure that lucrative contract is probably the nadir of my career. It will be difficult to bounce back from that.
We’re definitely not yet at the nadir of the crisis because things are continuing to get worse.