Vaccine

Definition

Vaccine is a noun referring to a preparation of weakened, killed, or fragmentary pathogens (or their products) administered to stimulate the immune system to develop protection against a specific disease.

Parts of Speech

• Noun

Pronunciation

American English

• IPA: /ˈvæk.siːn/
• Respelling: VAK-seen

British English

• IPA: /ˈvæk.siːn/
• Respelling: VAK-seen

Etymology

Early 19th century: from French vaccin ‘virus used for inoculation,’ from Latin vaccinus ‘of or from cows,’ from vacca ‘cow,’ after Edward Jenner’s use of cowpox to immunize against smallpox.

Derivatives

• vaccinate (verb)
• vaccinated (adjective; verb past)
• vaccinating (verb gerund)
• vaccination (noun)
• vaccinator (noun)

Synonyms

• inoculation
• immunization
• jab (British informal)
• shot (American informal)

Antonyms

• None

Usage

The noun "vaccine" is used in medical, public health, and scientific contexts to refer to agents that induce immunity against infectious diseases. For example, "She received her annual flu vaccine at the clinic," or "Global vaccine campaigns eradicated smallpox in 1980."

Related Terms

• Immunization: The process by which a person becomes protected against a disease.
• Antigen: A substance that stimulates an immune response.
• Antibody: A protein produced by the immune system that neutralizes pathogens.
• Booster: An additional vaccine dose given after the initial dose to sustain immunity.
• Herd immunity: Community-level protection that arises when a sufficient proportion of individuals are immune.

Detailed Definitions

Noun

• A preparation of attenuated, killed, or component pathogens administered to induce immunity – designed to provoke an immune response without causing disease.
  • Example: "Children receive the measles vaccine as part of routine childhood immunizations."
• A dose or injection of such a preparation – the act or instance of administering the vaccine.
  • Example: "Health workers administered the COVID-19 vaccine to thousands of people at the mass clinic."