- An antibody formed in response to and capable of neutralizing a specific toxin of biological origin.
- An animal or human serum containing antitoxins. It is used in medicine to prevent or treat diseases caused by the action of biological toxins, such as tetanus, botulism, and diphtheria.
- A substance which neutralizes the action of a toxin or poisonous ptomaine; specifically, a substance developed in the body of an animal by inoculation with the germs of diphtheria, which enables it to tolerate this poison.
- A substance which neutralizes the action of a poison.
- Specifically: The antibody to a toxin of bacterial or related origin which is produced as the result of immunization with the corresponding toxin. Examples are the diphtheria antitoxin and the tetanus antitoxin.
- In <em>botany</em>, a substance secreted by a plant which protects it against destructive microbes.
- A substance (sometimes the product of a specific micro-organism and sometimes naturally present in the blood or tissues of an animal), capable of producing immunity from certain diseases, or of counteracting the poisonous effects of pathogenic bacteria.
- An <xref>antibody</xref> that is capable of neutralising specific toxins that are causative agents of disease.
- an antibody that can neutralize a specific toxin