Source : Webster's Revised Unabridged Dictionary (1913)

Trachea \Tra"che*a\, n.; pl. {Trache[ae]}. [NL.,from L. trachia,
   Gr. trachei^a (sc. ? windpipe), from ? rough, rugged: cf. F.
   trach['e]e.]
   1. (Anat.) The windpipe. See Illust. of {Lung}.

   2. (Zo["o]l.) One of the respiratory tubes of insects and
      arachnids.

   3. (Bot.) One of the large cells in woody tissue which have
      spiral, annular, or other markings, and are connected
      longitudinally so as to form continuous ducts.

Source : WordNet®

trachea
     n 1: membranous tube with cartilaginous rings that conveys
          inhaled air from the larynx to the bronchi [syn: {windpipe}]
     2: one of the tubules forming the respiratory system of most
        insects and many arachnids
     [also: {tracheae} (pl)]

tracheae
     See {trachea}