'Lady's thumb' definitions:

Definition of 'Lady's thumb'

From: GCIDE
  • Lady's thumb \La"dy's thumb"\ (l[=a]"d[i^]z th[u^]m") n. (Bot.) An annual weed (Polygonum Persicaria), having a lanceolate leaf with a dark spot in the middle. [1913 Webster] Lady's traces