沉着 (chén zhuó): steady; calm and collected; not nervous

Facing a sudden fire, he remained very calm and quickly directed everyone to evacuate through the safe exit.

Even when she encountered a difficult problem she couldn't solve on the college entrance exam, she stayed calm and skipped it to do the later questions first.

As an emergency room doctor, he faces various urgent situations every day, but always handles each patient calmly and steadily.

In a fierce debate competition, when the opponent suddenly raised a sharp question, she thought calmly for a few seconds and then gave a powerful answer.