The Collaborative International Dictionary of English v.0.48:

Lady's mantle \La"dy's man"tle\ (l[=a]"d[i^]z m[a^]n"t'l).
   (Bot.)
   A genus of rosaceous herbs (Alchemilla), esp. the European
   Alchemilla vulgaris, which has leaves with rounded and
   finely serrated lobes.
   [1913 Webster]