Reference
Definition
What the word means. This is not a work instruction.
Grease duct carries grease-laden exhaust and is a fire-risk system. Material, welding, slope, cleanouts, access, clearance to combustibles, fire wrap, and inspection all matter. Do not modify it like regular duct.
Grease duct mistakes can become fire, inspection, and teardown problems. Ask before changing anything.
This term belongs to rated, life-safety, grease, or structural work. Knowing the word is fine. Doing the work is a red-lane call — get direction before you touch it.