How could you define bias?

prejudice in favor of or against one thing, person, or group compared with another, usually in a way considered to be unfair.

There is actually 3 ways to define the word Bias, so here's the definitions

1. prejudice in favor of or against one thing, person, or group compared with another, usually in a way considered to be unfair.

2. in some sports, such as lawn bowling, the irregular shape given to a ball. verb

3. cause to feel or show inclination or prejudice for or against someone or something