uneven parallel bars vs uneven bars

uneven parallel bars and uneven bars both are nouns.

Word	Noun	Adjective	Verb	Adverb
uneven parallel bars	Yes	No	No	No
uneven bars	Yes	No	No	No

As nouns, uneven parallel bars and uneven bars are synonyms defined as:

uneven parallel bars and uneven bars: a pair of parallel bars set at different heights; used in women's gymnastics

uneven parallel bars (noun)	uneven bars (noun)
a pair of parallel bars set at different heights; used in women's gymnastics	a pair of parallel bars set at different heights; used in women's gymnastics