Biological is the adjectival form of "biology", the study of life.
Biological may also refer to:
Biological agent, an infectious disease or toxin that can be used in bioterrorism or biological warfare Biological process Biological relationship, a measure of the degree of consanguinity
See also Biologic (disambiguation) Biological material (disambiguation) Biological warfare Biopharmaceutical, a drug that is synthesized from living organisms or their products and used as a medical treatment Organic (disambiguation)