In archaeology, debitage is all the material produced during the process of lithic reduction – the production of stone tools and weapons by knapping stone. This assemblage may include the different kinds of lithic flakes and lithic blades, but most often refers to the shatter and production debris, and production rejects.

In archaeology, in particular of the Stone Age, lithic reduction is the process of fashioning stones or rocks from their natural state into tools or weapons by removing some parts. It has been intensely studied and many archaeological industries are identified almost entirely by the lithic analysis of the precise style of their tools and the chaîne opératoire of the reduction techniques they used.