concern vs allude

concern is a noun but allude is not a noun.

Word	Noun	Adjective	Verb	Adverb
concern	Yes	No	Yes	No
allude	No	No	Yes	No

concern (noun)	allude (noun)
something that interests you because it is important or affects you
something or someone that causes anxiety; a source of unhappiness
a feeling of sympathy for someone or something
an anxious feeling
a commercial or industrial enterprise and the people who constitute it

concern (verb)	allude (verb)
be relevant to	make a more or less disguised reference to
be on the mind of