'Ventilator' definitions:

Definition of 'ventilator'

(from WordNet)
noun
A device (such as a fan) that introduces fresh air or expels foul air
noun
A device that facilitates breathing in cases of respiratory failure [syn: breathing device, breathing apparatus, breathing machine, ventilator]

Definition of 'Ventilator'

From: GCIDE
  • Ventilator \Ven"ti*la`tor\, n. [Cf. F. ventilateur, L. ventilator a winnower.] A contrivance for effecting ventilation; especially, a contrivance or machine for drawing off or expelling foul or stagnant air from any place or apartment, or for introducing that which is fresh and pure. [1913 Webster]

Synonyms of 'ventilator'

From: Moby Thesaurus