落ち着く
おちつく (ochitsuku)
to calm down, to settle down
verb (godan)
Example
試験の前に深呼吸をして落ち着いた。
しけんのまえにしんこきゅうをしておちついた。
Shiken no mae ni shinkokyuu wo shite ochitsuita.
I took a deep breath and calmed down before the exam.
This verb can describe both emotional states (calming down) and physical situations (settling into a place). Very useful for expressing stress management and finding stability.