Green’s Dictionary of Slang

(US drugs) cocaine, as in Bolivian marching powder n. or Peruvian marching powder.

1984		J. McInerney Bright Lights, Big City 2: Your brain at this moment is composed of brigades of tiny Bolivian soldiers [...] They need the Bolivian Marching Powder.
1996		P. Temple Bad Debts (2012) [ebook] Don’t be paranoid [...] It’s that marching powder you’re putting up your nose.
2000		J. Hawes Dead Long Enough 72: And what about the ... Columbian Marching Powder, shouted, then hissed Jan.
2001		ONDCP Street Terms 14: Marching dust — Cocaine.
2002		T. Dorsey Triggerfish Twist (2002) 341: Sharon has two hundred dollars of Peruvian Marching Dust and begins vacuuming at four o’clock.
2013		K. Sampson Killing Pool 58: From the way he’s driving the only thing that’s hit the mark is line after line of crazy marching powder.
2013		T. Dorsey Riptide Ultra-Glide 8: Coke, blow, flake, fluff, snow, marching dust, weasel powder, white death [etc].
2017		L. McInerney Blood Miracles 95: ‘Dan is getting altogether too fond of the marching powder’.
2020		G. Armstrong Young Team 133: Cafeine keeps me chargin, marchin powder keeps me dancin.