The Collaborative International Dictionary of English v.0.48:

Galban \Gal"ban\, Galbanum \Gal"ba*num\, n. [L. galbanum, Gr. ?,
   prob. from Heb. klekb'n?h: cf. F. galbanum.]
   A gum resin exuding from the stems of certain Asiatic
   umbelliferous plants, mostly species of Ferula. The Bubon
   Galbanum of South Africa furnishes an inferior kind of
   galbanum. It has an acrid, bitter taste, a strong, unpleasant
   smell, and is used for medical purposes, also in the arts, as
   in the manufacture of varnish.
   [1913 Webster]

WordNet (r) 3.0 (2006):

galbanum
    n 1: a bitter aromatic gum resin that resembles asafetida [syn:
         galbanum, gum albanum]

Easton's 1897 Bible Dictionary:

Galbanum
   Heb. helbenah, (Ex. 30:34), one of the ingredients in the holy
   incense. It is a gum, probably from the Galbanum officinale.