pickerel weed vs pickerelweed

pickerel weed and pickerelweed both are nouns.

Word	Noun	Adjective	Verb	Adverb
pickerel weed	Yes	No	No	No
pickerelweed	Yes	No	No	No

As nouns, pickerel weed and pickerelweed are synonyms defined as:

pickerel weed and pickerelweed: American plant having spikes of blue flowers and growing in shallow water of streams and ponds

Other synonyms of pickerel weed include Pontederia cordata, wampee.

pickerel weed (noun)	pickerelweed (noun)
American plant having spikes of blue flowers and growing in shallow water of streams and ponds	American plant having spikes of blue flowers and growing in shallow water of streams and ponds