Source : Webster's Revised Unabridged Dictionary (1913)

Biserrate \Bi*ser"rate\, a. [Pref. bi- + serrate.]
   1. (Bot.) Doubly serrate, or having the serratures serrate,
      as in some leaves.

   2. (Zo["o]l.) Serrate on both sides, as some antenn[ae].

Source : WordNet®

biserrate
     adj : having sawlike notches with the notches themselves similarly
           notched