The Collaborative International Dictionary of English v.0.48:

Verbenaceous \Ver`be*na"ceous\, a. (Bot.)
   Of or pertaining to a natural order (Verbenaceae) of
   gamopetalous plants of which Verbena is the type. The order
   includes also the black and white mangroves, and many plants
   noted for medicinal use or for beauty of bloom.
   [1913 Webster]