Lean or LEAN may refer to: Lean, also called "purple drank" "sizzurp," or "syrup," a recreational drug based on cough syrup Lean Laboratory, one which's focused on testing products and materials to deliver results in the most efficient way Lean manufacturing, process improvement discipline Lean software development, a translation of lean manufacturing principles to software development Lake trout (Salvelinus namaycush), a freshwater char living mainly in lakes in northern North America Lo… (More on Lean)