What's the difference between duet and nonet?

Duet

Definition:

(n.) A composition for two performers, whether vocal or instrumental.

Example Sentences:

(1) Both Jones and Cullum played a number of live tracks and sang a duet too, and this is the new programme's backbone.
(2) Alicia Keys and John Legend will duet on Let It Be , while John Mayer has agreed to join country singer Keith Urban for a rendition of Don't Let Me Down .
(3) The album is John Ogdon and Brenda Lucas's album Two Pianos, featuring duets by Mozart, Brahms and Lutosławski.
(4) There are highlights, among them the Foo Fighters' energising effect on a flagging audience, the noise the same audience makes when James Blunt appears - half cheer, half menacing low growl - and Madonna's unexpected duet with Eugene Hutz of thrillingly dissolute gypsy punks Gogol Bordello.
(5) In Sacred Monsters , her 2006 duet with Akram Khan, she explored fluidity of Asian movement and the challenge of the spoken work: in Robert Lepage’s Eonnagata she moved towards experimental theatre, and in her subsequent collaborations with Maliphant she developed a rich new palette of rapt, inwardly focused dance.
(6) This autumn’s project should deliver sparks as Khan creates and performs a duet with flamenco iconoclast Galván, exploring their fascination with rhythm, gesture, pattern and myth.
(7) This resulted in significant changes in frequency of duetting.
(8) He seems equally startled when talk turns to his 1989 remake of Something's Gotten Hold of My Heart, the duet with gay icon Marc Almond that returned him to the top of the British charts 15 years after his last hit.
(9) It is understood that the letter raises issues such as noise – in July Bruce Springsteen and Sir Paul McCartney's microphones were switched off during a duet due to curfew issues .
(10) Susan Boyle and Elvis Presley's duet, "Oh Come All Ye Faithful", is released today – all proceeds go to Save the Children .
(11) Within a week we’ve heard that the acclaimed singer-songwriters Ed Harcourt and Kathryn Williams are willing to sing our duet.
(12) He's had a few close shaves (a duet with Cocteau Twins' Liz Frazer and an appearance on The One Show spring to mind) but the idea of maintaining a fanbase, even a cult one, is alien to Lawrence.
(13) A film he was to star in about the Silk Road, written by Gulnara Karimova, the daughter of Uzbekistan's president, seems however to have broken down in the wake of bitter family infighting – but they'll always have the duet they recorded together, How Dare .
(14) Any Moldy Peach diehards balking at the idea of Green duetting with someone other than Dawson are missing out, though: this record sounds as though he and Shapiro have known each other for ever.
(15) I told him one day, 'Let's do a small duet of baritone and soprano,' and he said, 'No, no, my fans only know me as a rock singer and they will not recognise my voice if I sing in baritone.'
(16) Duets are Maliphant's forte – even his solos often feel like duets, in which one of the partners is light, space or sound.
(17) I've got a new duet, as we call them, out now, or coming out now.
(18) A couple of years later, Wright and Jack Anglin formed a duet act, Johnnie & Jack, and she toured with them in the then conventional role of the "girl singer".
(19) On Saturday's show, the four remaining finalists will compete with each other by singing solo and duetting with established acts before two rounds of voting leave two acts in a head-to-head on Sunday's show.
(20) Apart from a brief and unhappy appearance on the BBC's Just the Two of Us (a celebrity duet singing contest in which she was partnered with Alexander O'Neal) in 2006 – "Never again!"