Definition of "ventilation"

ventilation

/ˌvɛntɪˈleɪʃ(ə)n/

noun
countable and uncountable, plural ventilations
1. The replacement of stale or noxious air with fresh.
  Quotations
  So you punched out a window for ventilation. Was that before or after you noticed you were standing in a lake of gasoline?
  1991, Robert DeNiro (actor), Backdraft
2. The mechanical system used to circulate and replace air.
3. An exchange of views during a discussion.
4. The public exposure of an issue or topic.
  Quotations
  "No, Mr. Malone, I will place no restriction upon your correspondence, since the ventilation of the facts is the object of your journey; but I demand that you shall give no particulars as to your exact destination, and that nothing be actually published until your return."
  1912, Arthur Conan Doyle, The Lost World […], London, New York, N.Y.: Hodder and Stoughton
5. The bodily process of breathing; the inhalation of air to provide oxygen, and the exhalation of spent air to remove carbon dioxide.
6. (medicine) The mechanical system used to assist breathing.