noun
antigen
AN-ti-jen
Antigen (noun) means a substance that triggers an immune response, usually one from outside the body. Example: “The vaccine contains an antigen that prompts the body to make antibodies.”
noun
1
immunology A substance that triggers an immune response, usually one from outside the body.
"The vaccine contains an antigen that prompts the body to make antibodies."
"Each virus carries antigens on its surface."
"The test looks for antigens in a swab from the nose."
How to use antigen
Learner’s notesIn plain EnglishSomething that sets off your immune system.
When to use it
It is a scientific and medical term, though common in news about tests and vaccines.
Memory tip
Antigens provoke the response and antibodies answer it, so keep the two words distinct.
Trace the full origin ↓
Easily confused with
Common pairings
viral antigen
antigen test
surface antigen
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Fill the gap
Can you complete this real example?
The vaccine contains an _____ that prompts the body to make antibodies.
Etymology
Antigen comes from French antigène, formed from anti- and gène.
Frequently asked questions
What is an antigen?
An antigen is anything that sets off the body's immune system. It is usually foreign to the body, though not always.
What is the difference between an antigen and an antibody?
An antigen is what triggers an immune response, while an antibody is a protein the body makes in reaction to it.
What is the plural of antigen?
The plural is antigens.
What is the meaning of antigen?
"antigen" (noun) means a substance that triggers an immune response, usually one from outside the body.
