water hyacinth vs water orchid

water hyacinth and water orchid both are nouns.

Word	Noun	Adjective	Verb	Adverb
water hyacinth	Yes	No	No	No
water orchid	Yes	No	No	No

As nouns, water hyacinth and water orchid are synonyms defined as:

water hyacinth and water orchid: a tropical floating aquatic plant having spikes of large blue flowers; troublesome in clogging waterways especially in southern United States

Other synonyms of water hyacinth include Eichhornia crassipes, Eichhornia spesiosa.

water hyacinth (noun)	water orchid (noun)
a tropical floating aquatic plant having spikes of large blue flowers; troublesome in clogging waterways especially in southern United States	a tropical floating aquatic plant having spikes of large blue flowers; troublesome in clogging waterways especially in southern United States