A Bioweapon is a biological system, a form of life or a virus used for military purposes. This definition covers any such weapons used for any purpose, even the ones not directly harming and/or killing people such as agricultural pests or diseases intended to reduce the fighting power of the enemy's soldiers.[1]
In "The Expanse", the term is especially used for both the unmodified protomolecule and subsequently for the "protomolecule soldiers" created by a secret research program.