資料來源 : Webster's Revised Unabridged Dictionary (1913)

Air vessel \Air" ves`sel\
   A vessel, cell, duct, or tube containing or conducting air;
   as the air vessels of insects, birds, plants, etc.; the air
   vessel of a pump, engine, etc. For the latter, see {Air
   chamber}. The air vessels of insects are called trache[ae],
   of plants spiral vessels.