equanimity - Google Search
Evenminded endurance is called titiksha in Sanskrit. I have practiced this mental neutrality.
Paramahansa Yogananda • The Divine Romance: Collected Talks and Essays on Realizing God in Daily Life – Volume 2
The Greeks had a word for this: apatheia. It’s the kind of calm equanimity that comes with the absence of irrational or extreme emotions. Not the loss of feeling altogether, just the loss of the harmful, unhelpful kind. Don’t let the negativity in, don’t let those emotions even get started. Just say: No, thank you. I can’t afford to panic.
Ryan Holiday • The Obstacle Is the Way: The Timeless Art of Turning Trials into Triumph

How to stay calm (without any hacks)
This is all you need. https://t.co/RgVVVwBlpx
“Equanimity boils down to this:
Everything is great and I am ok.
Everything sucks and I am ok.”
– Jerry Colonna
Everything is great and I am ok.
Everything sucks and I am ok.”
– Jerry Colonna