Here's a breakdown:

* Flammability refers to the ease with which a substance will ignite and burn. It's often measured by how easily it can be ignited, how quickly it burns, and how much heat it generates.

* Combustibility is a closely related term that refers to the ability of a substance to burn.

While both terms are related, "flammability" is more commonly used to describe the relative ease with which a substance will burn.