Nickname for promethazine, also known as lean or sizzurp. Used as a recreational drug, and referenced by a ton of rappers in songs.

However, some artists just talk about using lean, while in reality they have never touched the stuff. (Drake aka Jimmy the cripple)
Tyrone: Eyy nigga you wanna drop a 4 in a 20oz?

Donavon: Yeah bluhh, Im finna trip off dat PROMETHALEAN naww mean nigga, naww mean?

Tyrone: Yee nigga I feel you, dat sizzurp gets me leaning like a mah fucker!
by Ghost OG July 20, 2011
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