The Collaborative International Dictionary of English v.0.48:

lady-of-the-night \lady-of-the-night\ n. (Bot.)
   A West Indian shrub (Brunfelsia americana) with fragrant
   showy yellowish-white flowers.

   Syn: lady of the night, Brunfelsia americana.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

lady-of-the-night
    n 1: West Indian shrub with fragrant showy yellowish-white
         flowers [syn: lady-of-the-night, Brunfelsia americana]