What does "testify" mean?

Testify: 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. Num. xxxv.

Additional senses

  1. 2.3. To declare a charge; to protest; to give information; to bear witness; -- with against. O Israel, . . . I will testify against thee. Ps. l.
  2. 3.I testified against them in the day wherein they sold victuals. Neh. xiii.
  3. 4.1. To bear witness to; to support the truth of by testimony; to affirm or declare solemny. We speak that we do know, and testify that we have seen; and ye receive not our witness. John iii.
  4. 5.2. (Law) To affirm or declare under oath or affirmation before a tribunal, in order to prove some fact.
  5. 6.In a testy manner; fretfully; peevishly; with petulance.

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