sisu

Sisu is a Finnish word variously translated as stoic determination, tenacity of purpose, grit, bravery, resilience, and hardiness. It is held by Finns to express their national character. It does not necessarily have a single-word literal equivalent in English, although tenacity, grit, resilience, and hardiness share similar meanings but do not necessarily imply stoicism or bravery.

In recent years, sociologists and psychologists have conducted research on sisu, attempting to quantify it and identify its effects, beneficial and harmful, in both individuals and populations.