phew

interjection
  1. An exclamation used to express relief, fatigue, surprise, or disgust. interjection
    Phew, that was a close call!
    After running the marathon, he sat down and said, 'Phew, I'm exhausted.'
  2. An expression of relief after a tense or difficult situation. interjection
    The test results came back negative. Phew!
    She finally finished her presentation and let out a 'Phew!' of relief.