Definitions
1.NounA repeated melody line in a song, usually instrumental but sometimes vocal."Listen to one of the greatest guitar riffs of all time!"
2.NounA clever or witty remark.
3.NounA variation on something.
4.NounA spoof.
5.VerbTo improvise in the performance or practice of an art, especially by expanding on or making novel use of traditional themes.
6.VerbTo riffle.
7.VerbTo tell jokes over a movie or similar performance.
8.NounThe belly; the bowels.