Green’s Dictionary of Slang

to waste time, to act aimlessly.

1969		N. Cohn Awopbop. (1970) 158: The right moment went and still they fannied about.
2000		Hip-Hop Connection Jan. 74: Don’t fanny about on the sidelines, get stuck in.
2004		I. Rankin Fleshmarket Close (2005) 147: ‘You better get her that phone number, pal. And no more fannying around’.
2006		D. Mitchell Black Swan Green 308: I ain’t fannyin’ about fer the likes o’ you.
2009		T. Black Gutted 126: I was an economic migrant [...] I had no feckin’ time or money for fannying about on tour buses.
2012		(con. 1980s) I. Welsh Skagboys 168: There was no point fannyin about.
2016		Twitter 27 Nov. 🌐 If you want to know yours [i.e. surname], while I'm fannying around here, let me know!