Green’s Dictionary of Slang

slaughterer n.

[such one-sided deals slaughter the sellers]

a dealer who buys from small makers at extremely low prices.

[UK](con. 1840s–50s) H. Mayhew London Labour and London Poor I 333/1: The ‘slaughterers’ who supply all the goods required for the furniture of a house, buy at ‘starvation prices’.