The Collaborative International Dictionary of English v.0.48:

Benzoin \Ben*zoin"\ (b[e^]n*zoin"), n. [Cf. F. benjoin, Sp.
   benjui, Pg. beijoin; all fr. Ar. lub[=a]n-j[=a]w[imac]
   incense form Sumatra (named Java in Arabic), the first
   syllable being lost. Cf. Benjamin.]

   Note: [Called also benjamin.]
   1. A resinous substance, dry and brittle, obtained from the
      Styrax benzoin, a tree of Sumatra, Java, etc., having a
      fragrant odor, and slightly aromatic taste. It is used in
      the preparation of benzoic acid, in medicine, and as a
      perfume.
      [1913 Webster]

   2. A white crystalline substance, C14H12O2, obtained from
      benzoic aldehyde and some other sources.
      [1913 Webster]

   3. (Bot.) The spicebush (Lindera benzoin).
      [1913 Webster]

   Flowers of benzoin, benzoic acid. See under Benzoic.
      [1913 Webster]

WordNet (r) 3.0 (2006):

benzoin
    n 1: gum resin used especially in treating skin irritation [syn:
         benzoin, gum benzoin, benjamin, gum benjamin, asa
         dulcis]
    2: used in some classifications for the American spicebush and
       certain other plants often included in the genus Lindera
       [syn: Benzoin, genus Benzoin]