The Collaborative International Dictionary of English v.0.48:

Indazole \In"da*zole\, n. [Indol + azote.] (Chem.)
   A bicyclic nitrogenous compound, C7H6N2, analogous to
   indole, having a benzene ring fused to a pyrazole ring;
   called also indazol and benzopyrazole. It can be produced
   from a diazo derivative of cinnamic acid.
   [1913 Webster +PJC]