From HomoExcelsior

1. A mechanism or device by which something is conveyed or conducted. 2. A person or an animal that shows no symptoms of a disease but harbors the infectious agent of that disease and is capable of transmitting it to others. 3. An individual that carries one gene for a particular recessive trait. A carrier does not express the trait but, when mated with another carrier, can produce offspring that do. 4. A carrier wave. 5. A charge-carrying entity, especially an electron or a hole in a semiconductor.

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