The definition of unfair is something that is not in accordance with justice or that is not kind or impartial.(adjective)
When an inadequate and ineffective worker gets promoted instead of you because he happens to be a friend of the boss, this is an example of something that would be described as unfair.
See unfair in Webster's New World College Dictionary
Origin: ME < OE unfæger, unfair, ugly < un-, not + fæger, fair
See unfair in American Heritage Dictionary 4
adjective un·fair·er, un·fair·est
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