dendrobium vs orchid

dendrobium and orchid both are nouns.

Word	Noun	Adjective	Verb	Adverb
dendrobium	Yes	No	No	No
orchid	Yes	No	No	No

As nouns, orchid is a hypernym of dendrobium; that is, orchid is a word with a broader meaning than dendrobium:

dendrobium: a plant of the genus Dendrobium having stems like cane and usually showy racemose flowers
orchid: any of numerous plants of the orchid family usually having flowers of unusual shapes and beautiful colors

Other hypernyms of dendrobium include orchidaceous plant.

dendrobium (noun)	orchid (noun)
a plant of the genus Dendrobium having stems like cane and usually showy racemose flowers	any of numerous plants of the orchid family usually having flowers of unusual shapes and beautiful colors