Green’s Dictionary of Slang

scale v.³

(drugs) to weigh a measure of a drug.

1997

(con. 1970s) G. Pelecanos King Suckerman (1998) 40: I don’t need to scale it out. it’s got good weight.

In compounds

scale boy (n.)

(drugs) one who weighs and measures out portions of a drug.

1992

T. Williams Crackhouse 82: In the spot, you have three people: the scale boy, the doorman, and the guard.

In phrases