Testify (?), v. i. [imp. & p. p. Testified (?); p. pr. & vb. n. Testifying (?).] [OF. testifier, L. testificari; testis a witness + -ficare (in comp.) to make. See -fy, and cf. Attest, Contest, Detest, Protest, Testament.] 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.
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Jesus . . . needed not that any should testify of man, for he knew what was in man. John ii. 25.
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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.
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One witness shall not testify against any person to cause him to die. Num. xxxv. 30.
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3. To declare a charge; to protest; to give information; to bear witness; -- with against.
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O Israel, . . . I will testify against thee. Ps. l. 7.
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I testified against them in the day wherein they sold victuals. Neh. xiii. 15.
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Testify, adv. In a testy manner; fretfully; peevishly; with petulance.
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