The Collaborative International Dictionary of English v.0.48:

Solanaceous \Sol`a*na"ceous\, a. (Bot.)
   Of or pertaining to plants of the natural order Solanaceae,
   of which the nightshade (Solanum) is the type. The order
   includes also the tobacco, ground cherry, tomato, eggplant,
   red pepper, and many more.
   [1913 Webster]

WordNet (r) 3.0 (2006):

solanaceous
    adj 1: of or relating to plants of the family Solanaceae (the
           potato family)