biological
Meaning of biological: Three different meanings share one word, and only the surrounding sentence shows whether life science, a class of medicine, or family descent is meant.
Definition of biological
Biological means relating to life and to living things. In medicine the word narrows: a biological product is one made by or drawn from a living organism or its cells, rather than built by chemical synthesis. The same adjective carries an unrelated everyday sense, describing family relationships based on descent rather than on adoption.
What is a biological medicine?
A biological drug, usually shortened to a biologic, is manufactured inside living systems: bacteria, yeast, cultured animal cells, and occasionally whole plants or animals. Insulin, vaccines, antibodies raised against a single target, clotting factors, interleukins and cell therapies all belong to the group, and so do blood products such as transfused red cells and proteins separated from plasma. The category is defined by the source rather than by what the product treats, which is why it cuts across almost every specialty.
How do they differ from ordinary drugs?
| Biological | Small molecule drug | |
|---|---|---|
| Made by | Living cells or organisms | Chemical synthesis |
| Structure | Large folded proteins, often with sugar chains attached | Small, simple, completely specified |
| Given by | Usually injection or infusion, since digestion destroys most | Frequently swallowed |
| Copies | Biosimilars: highly similar but never identical | Generics: chemically identical |
| Handling | Often needs cold storage and careful handling | Usually stable at room temperature |
The row on copies causes the most confusion. A living cell line produces slight variation from batch to batch, so a competing manufacturer cannot reproduce a biologic exactly, only closely enough to behave the same way. That is why the copies are called biosimilars rather than generics, and why they are approved through a separate route with its own comparison studies.
What are the other senses of the word?
Outside pharmacy the adjective keeps its wide meaning: a biological process is one occurring in a living organism, biological science is the study of life, and a biological sample is material taken from a body. Related terms narrow it again, so biological therapy means treatment using substances derived from living sources, frequently to prompt the immune system to act against disease. In everyday speech, biological parent, child or sibling describes a relationship by descent rather than one created through adoption, fostering or marriage. That sense matters clinically whenever an inherited condition is traced, since only the relationship by descent carries shared genes. Nothing but context separates the three.
Also known as
Used in a sentence
The treatment plan included a biological agent targeting a specific protein involved in the disease process.
Good to know
Biological can describe a medicine made from a living source or, in an unrelated sense, a relationship by descent, so the meaning depends on the surrounding context rather than on the word alone.
Word origin
Where “biological” comes from
Formed from Greek bios, meaning life, and logos, meaning study or reason, with the adjectival suffix -ical.