1.To make a solemn declaration, verbal or written, to establish some fact; to give testimony for the purpose of communicating to others a knowledge of something not known to them. "Jesus... needed not that any should testify of man, for he knew what was in man."
2.(Law) To make a solemn declaration under oath or affirmation, for the purpose of establishing, or making proof of, some fact to a court; to give testimony in a cause depending before a tribunal. "One witness shall not testify against any person to cause him to die."
3.To declare a charge; to protest; to give information; to bear witness; with against. "O Israel,... I will testify against thee." "I testified against them in the day wherein they sold victuals."
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