Definition of ladies' tresses in US English:

ladies' tresses

(also lady's tresses)

plural noun

  • usually treated as singular A short orchid with small white flowers arranged in a single or double spiral, growing chiefly in north temperate regions.

    Genus Spiranthes (and Goodyera), family Orchidaceae: several species, including the slender ladies' tresses (S. gracilis) of North America