orchid vs orchidaceous plant

orchid and orchidaceous plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
orchid	Yes	No	No	No
orchidaceous plant	Yes	No	No	No

As nouns, orchid and orchidaceous plant are synonyms defined as:

orchid and orchidaceous plant: any of numerous plants of the orchid family usually having flowers of unusual shapes and beautiful colors

orchid (noun)	orchidaceous plant (noun)
any of numerous plants of the orchid family usually having flowers of unusual shapes and beautiful colors	any of numerous plants of the orchid family usually having flowers of unusual shapes and beautiful colors