1. A protein found on the surface of influenza viruses and other pathogens that binds to red blood cells and enables the virus to attach to and infect host cells.
Usage: technical; medical; also spelled hemagglutinin in U.S. English

Examples

• Haemagglutinin is one of the two main surface proteins of the influenza virus.
• The H1N1 designation refers to the type of haemagglutinin present on that flu strain.
• Researchers study haemagglutinin to develop more effective flu vaccines.
• Antibodies against haemagglutinin can help the immune system recognize and fight influenza infection.
• The structure of haemagglutinin determines which cells the virus can infect.