Definition

Noun: A form of acquired immunity in which the body's own immune system is stimulated to produce antibodies and memory cells against a specific disease-causing antigen, providing long-lasting protection.

Usage

This term is used in medical and biological contexts to describe the immunity that develops after exposure to a pathogen or through vaccination. It contrasts with passive immunity, which involves receiving antibodies from an external source.

Examples

• Vaccination induces active immunity against diseases like measles and polio.
• Recovering from an infection often results in active immunity to that particular pathogen.
• The goal of many vaccines is to stimulate active immunity without causing the actual disease.

Advanced Usage

• Naturally acquired active immunity: Immunity gained after recovering from an actual infection.
• Artificially acquired active immunity: Immunity induced by vaccines, which contain weakened or inactivated antigens.

Variants and Related Words

• Immunity (n): The general ability of an organism to resist a particular infection or toxin.
• Active Immunization (n): The process of inducing active immunity, typically through vaccination.

Synonyms

• Acquired immunity (specific to this form)
• Adaptive immunity (broader category encompassing active immunity)

Antonyms

• Passive immunity
• Innate immunity

Noun

1. a form of acquired immunity in which the body produces its own antibodies against disease-causing antigens