Green’s Dictionary of Slang

gaffle n.

[gaffle v.]

1. (US black) defeat, failure, betrayal.

‘Christmas Energy’ in World and I Dec. 🌐 I had purchased them in advance, because no parent wants to be accused of stealing the joy of Christmas by giving a batteryless Photon laser gun or talking Teddy Ruxpin or gigantic ‘portable’ radio. Such a gaffle could bring the child welfare folks to your door with charges of cruelty and neglect.

2. (US drugs) fake crack cocaine.

Reinaman & Levine Crack in America 98: The last tenant was a crack dealer who repeatedly sold gaffle (fake or ‘bunk’ crack).
D. Stannard-Friel City Baby and Star 47: They have good enough stuff, won’t stick her with gaffle. Bunk. [...] Bad shit, fake crack.