A crust that forms over a wound or sore during healing. After she fell off her bike, a scab formed on her knee.
A person who works despite an ongoing strike; a strikebreaker. The union members were upset with the scabs who crossed the picket line.
A plant disease characterized by crusty spots on leaves, stems, or fruit, caused by a fungus or bacterium. The apple orchard suffered from scab, affecting the quality of the fruit.
A contemptible or disagreeable person. I can’t believe that scab lied to everyone about what really happened.