An all-purpose word that can be tacked on to the end of any sentence whilst you're in London, innit. It's now become so commonplace that it's not unheard of for visitors to the city to think that the correct pronunciation is "Londoninnit". Although innit may once have derived from isn't it? -- and ultimately from the second- and third-generation Asian immigrant population's overuse of that phrase -- it no longer really has that meaning. A similarity can be drawn with the technique of adding "you know" to every other sentence.