What is A Cappella?
1.
A genre of music using no instruments besides vocals.
Examples of groups are Rockapella, Three Men and a Tenor, and Ascending A Cappella.
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2.
"A capella" definition is wrong. Not usually used by rappers, but rather by people that actually...sing (and sing well) without instrumental accompaniment. Please see
...for more enlightenment on what a cappella is.
"Hey guys, let's sing real a cappella, with no instrumental accompaniment. And better yet, let's actually sing and use musical notes in our music and not chant simple rhymes and curse words in a monotone like the music artist b rabbit does in 8 Mile!"
"Sounds great! Wait, b rabbit is a music artist? Since when?"
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3.
voice music without instrumental accompaniment.
"The band died when they cut the power but Sid just sang a cappella like he never heard them anyway."
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4.
To fuck without condom
There was no place to get a condom, so we did it a cappella.
See