silversides vs silverside

silversides and silverside both are nouns.

Word	Noun	Adjective	Verb	Adverb
silversides	Yes	No	No	No
silverside	Yes	No	No	No

As nouns, silversides and silverside are synonyms defined as:

silversides and silverside: small fishes having a silver stripe along each side; abundant along the Atlantic coast of the United States

silversides (noun)	silverside (noun)
small fishes having a silver stripe along each side; abundant along the Atlantic coast of the United States	small fishes having a silver stripe along each side; abundant along the Atlantic coast of the United States
the common North American shiner