Source : Webster's Revised Unabridged Dictionary (1913)

Asafetida \As`a*fet"i*da\, Asafoetida \As`a*f[oe]t"i*da\, n.
   [Asa + L. foetidus fetid.]
   The fetid gum resin or inspissated juice of a large
   umbelliferous plant ({Ferula asaf[oe]tida}) of Persia and the
   East Indies. It is used in medicine as an antispasmodic.
   [Written also {assaf[oe]tida}.]

Source : WordNet®

asafetida
     n : the brownish gum resin of various plants; has strong taste
         and odor; formerly used as an antispasmodic [syn: {asafoetida}]