moccasin flower vs lady slipper

moccasin flower and lady slipper both are nouns.

Word	Noun	Adjective	Verb	Adverb
moccasin flower	Yes	No	No	No
lady slipper	Yes	No	No	No

As nouns, lady slipper is a hypernym of moccasin flower; that is, lady slipper is a word with a broader meaning than moccasin flower:

moccasin flower: once common rose pink woodland orchid of eastern North America
lady slipper: any of several chiefly American wildflowers having an inflated pouchlike lip; difficult or impossible to cultivate in the garden

Other hypernyms of moccasin flower include ladies' slipper, lady's-slipper, lady's slipper, lady-slipper, slipper orchid.

moccasin flower (noun)	lady slipper (noun)
once common rose pink woodland orchid of eastern North America	any of several chiefly American wildflowers having an inflated pouchlike lip; difficult or impossible to cultivate in the garden