vinca minor

from WordNet (r) 3.0 (2006)

Vinca minor
    n 1: widely cultivated as a groundcover for its dark green shiny
         leaves and usually blue-violet flowers [syn: {myrtle},
         {Vinca minor}]

from The Collaborative International Dictionary of English v.0.48

Periwinkle \Per"i*win`kle\, n. [OE. pervenke, AS. pervince, fr.
   L. pervinca.] (Bot.)
   A trailing herb of the genus {Vinca}.
   [1913 Webster]

   Note: The common perwinkle ({Vinca minor}) has opposite
         evergreen leaves and solitary blue or white flowers in
         their axils. In America it is often miscalled {myrtle}.
         See under {Myrtle}.
         [1913 Webster]