plural form vs rudiments

plural form and rudiments both are nouns.

Word	Noun	Adjective	Verb	Adverb
plural form	Yes	No	No	No
rudiments	Yes	No	No	No

plural form (noun)	rudiments (noun)
the form of a word that is used to denote more than one	the elementary stages of any subject (usually plural)
	a statement of fundamental facts or principles