Source : Webster's Revised Unabridged Dictionary (1913)

Galanga \Ga*lan"ga\, Galangal \Ga*lan"gal\, n.[OE. galingale,
   OF. galingal, garingal, F. galanga (cf. Sp. galanga), prob.
   fr. Ar. khalanj?n. ]
   The pungent aromatic rhizome or tuber of certain East Indian
   or Chinese species of {Alpinia} ({A. Galanga} and {A.
   officinarum}) and of the {K[ae]mpferia Galanga}), -- all of
   the Ginger family.

Source : WordNet®

galangal
     n 1: southeastern Asian perennial with aromatic roots [syn: {Alpinia
          galanga}]
     2: European sedge having rough-edged leaves and spikelets of
        reddish flowers and aromatic roots [syn: {galingale}, {Cyperus
        longus}]