The Collaborative International Dictionary of English v.0.48:

airway \airway\ n.
   1. a duct that provides ventilation, as in mines.

   Syn: air passage, air duct.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

airway
    n 1: a duct that provides ventilation (as in mines) [syn: air
         passage, air duct, airway]
    2: a designated route followed by airplanes in flying from one
       airport to another [syn: air lane, flight path, airway,
       skyway]
    3: the passages through which air enters and leaves the body
       [syn: respiratory tract, airway]
    4: a commercial enterprise that provides scheduled flights for
       passengers [syn: airline, airline business, airway]

Moby Thesaurus II by Grady Ward, 1.0:

29 Moby Thesaurus words for "airway":
   air duct, air hole, air lane, air line, air passage, air route,
   air shaft, air tube, blowhole, breathing hole, corridor, lane,
   louver, louverwork, naris, nostril, path, shaft, spilehole,
   spiracle, touchhole, transom, vent, ventage, venthole, ventiduct,
   ventilating shaft, ventilator, wind tunnel