The term has different meanings in different contexts. As a few examples:
In agriculture, biosecurity usually refers to efforts to protect food crops or livestock from pests, invasive species, and infectious disease.
In national security, biosecurity usually refers to preventing theft, diversion, or deliberate malicious use of biological knowledge. materials or technologies.
In many non-English languages, biosecurity is not commonly distinguished from biosafety, or is seen as a sub-category of it.
Within the effective altruism community, biosecurity has been characterized as primarily covering "natural pandemics", "bioterrorism and the intentional deployment of biological weapons", and "dual use research and the possibility of accidental deployment of biological agents." (Open Philanthropy 2020)