Definition of "malarky"

'Smuggling,' she said. 'has a fine romantic ring about it—once aboard the lugger, you heave ho and all that kind of malarky. [...]'

1968, Margery Allingham, “The String Man”, in Cargo of Eagles, London: Chatto & Windus; republished London: Vintage, 2016, page 91

There's mischiefs and malarkies / But no queers, or yids, or darkies. / Within this bastard's carnival, / This vicious cabaret!

1983 August, Alan Moore, David Lloyd, illustrator, “V for Vendetta: This Vicious Cabaret”, in Dez Skinn, editor, Warrior, number 12, London: Quality Communications, pages 92–93; quoted in Lance Parkin, Magic Words: The Extraordinary Life of Alan Moore, London: Aurum Press, 2013, page 196

A company that makes a fetish of never exceeding the budget invites game-playing and other malarky. It is easy to forget the obvious: that it involves no skill to come in on time and under budget if the schedule and budget are generous enough.

1993, Richard Barry, “Budgeting”, in The Management of International Oil Operations, Tulsa, Ok.: PennWell Books, page 331