skittles vs ninepins

skittles and ninepins both are nouns.

Word	Noun	Adjective	Verb	Adverb
skittles	Yes	No	No	No
ninepins	Yes	No	No	No

As nouns, skittles and ninepins are synonyms defined as:

skittles and ninepins: a bowling game that is played by rolling a bowling ball down a bowling alley at a target of nine wooden pins

skittles (noun)	ninepins (noun)
a bowling game that is played by rolling a bowling ball down a bowling alley at a target of nine wooden pins	a bowling game that is played by rolling a bowling ball down a bowling alley at a target of nine wooden pins