D defs.my
Entry 2 senses Webster, 1913

hyperventilation

· IPA /haɪ.pə(ɹ)ˌvɛntəˈleɪ.ʃən/
01 n. The act or process of hyperventilating; breathing rapidly and deeply.
  1. 1.
    The act or process of hyperventilating; breathing rapidly and deeply.
  2. 2.
    A condition in which alveolar carbon dioxide concentration is markedly lower than normal, usually due to breathing rapidly and deeply.(Med.)