plural form vs topside

plural form and topside both are nouns.

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

plural form (noun)	topside (noun)
the form of a word that is used to denote more than one	(usually plural) weather deck; the part of a ship's hull that is above the waterline