Antibody
Etymology
A direct translation of German "Antikörper," from "anti-" (against) and "Körper" (body), coined around 1900 as immunology took shape. The "body" here is the microscopic particle it opposes, not the human body that produces it.
noun · /AN-tih-bod-ee/
A Y-shaped protein the immune system makes to recognize and stick to one specific invader.
What it names
Use it for the body’s custom-built, targeted recognition tool — the lock cut to fit one particular key.
Example
After the infection cleared, her blood still carried antibodies ready to catch the same virus.
Related idea
Keep three near-twins straight: an antigen is the foreign marker that triggers a response, an antibody is the protein your body makes to match that antigen, and an antibiotic is a drug — not made by you — that kills bacteria. Antibodies are yours; antibiotics come from a bottle.