empty and meaningless talk; so on and so forth; used for implying that what is being said is not worth the saying or has been said too often already UK
[M]y rents were telling me off... nim nim nim! — Lucy van Amerongen, TheA-ZofTeenTalk, p. 24, 2007
Andy Parsons: “Do what? Innit. Nim nim nim.” Frankie Boyle: “What is nim nim nim?” Andy Parsons: “You’re not in with the kids, are ya?” — MocktheWeek, 13 September 2007