Entry in progress—B.P.
(Oxford English Dictionary)
U.S. slang var. scoff v.2 1. Also absol. and const. up and down.
1960 R. G. Reisner Jazz Titans 164 Scarf, eat.
1968 C. Armstrong Balloon Man viii. 98 They don’t want to faint from hunger, so‥they scarf up what they call a bite before they go.
1974 Black World June 77/1 King Dust would sit there, ‘scarfing’, as he called it, in silence.
1975 High Times Dec. 80/3, I can pick jimsonweed and chop it up and scarf it down as well as the next guy.