Ventilator

n. fan, device which circulates the air; machine which helps a person breathe, respirator

A medical ventilator may be defined as an automatic machine designed to mechanically move breatheable air into and out of the lungs, to provide respiration for a patient who is physically unable to breathe, or breathing insufficiently. Ventilators are chiefly used in intensive care medicine, home care, and emergency medicine (as standalone units) and in anesthesia (as a component of an anesthesia machine).
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Ventilator /ven·ti·la·tor/ 1. an apparatus for qualifying the air breathed through it. 2. a device for giving artificial respiration or aiding in [more]Ventilator - Community and Resources

Noun
1. a device (such as a fan) that introduces fresh air or expels foul air
(hypernym) device
(part-holonym) ventilation, ventilation system, ventilating system
(part-meronym) air filter, air cleaner
(derivation) ventilate
2. a device that facilitates breathing in cases of respiratory failure
(synonym) breathing device, breathing apparatus, breathing machine
(hypernym) device
(hyponym) aqualung, Aqua-Lung, scuba

n. ventilator, fan, aerator, device that produces currents of air