lady's tresses vs orchid

lady's tresses and orchid both are nouns.

Word	Noun	Adjective	Verb	Adverb
lady's tresses	Yes	No	No	No
orchid	Yes	No	No	No

As nouns, orchid is a hypernym of lady's tresses; that is, orchid is a word with a broader meaning than lady's tresses:

lady's tresses: an orchid of the genus Spiranthes having slender often twisted spikes of white flowers
orchid: any of numerous plants of the orchid family usually having flowers of unusual shapes and beautiful colors

Other hypernyms of lady's tresses include orchidaceous plant.

lady's tresses (noun)	orchid (noun)
an orchid of the genus Spiranthes having slender often twisted spikes of white flowers	any of numerous plants of the orchid family usually having flowers of unusual shapes and beautiful colors