Source : Webster's Revised Unabridged Dictionary (1913)

Teeth \Teeth\, v. i. [imp. & p. p. {Teethed}; p. pr. & vb. n.
   {Teething}.]
   To breed, or grow, teeth.

Teething \Teeth"ing\, n.
   The process of the first growth of teeth, or the phenomena
   attending their issue through the gums; dentition.

Source : WordNet®

teething
     n : the eruption through the gums of baby teeth [syn: {dentition},
          {odontiasis}]