The Collaborative International Dictionary of English v.0.48:

Verify \Ver"i*fy\ (v[e^]r"[i^]*f[imac]), v. t. [imp. & p. p.
   Verified; p. pr. & vb. n. Verifying.] [F. v['e]rifier,
   LL. verificare, from L. verus true + -ficare to make. See
   Very, and -fy.]
   1. To prove to be true or correct; to establish the truth of;
      to confirm; to substantiate.
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            This is verified by a number of examples. --Bacon.
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            So shalt thou best fulfill, best verify.
            The prophets old, who sung thy endless reign.
                                                  --Milton.
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   2. To confirm or establish the authenticity of by examination
      or competent evidence; to authenticate; as, to verify a
      written statement; to verify an account, a pleading, or
      the like.
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            To verify our title with their lives. --Shak.
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   3. To maintain; to affirm; to support. [Obs.] --Shak.
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WordNet (r) 3.0 (2006):

verifying
    adj 1: serving to support or corroborate; "collateral evidence"
           [syn: collateral, confirmative, confirming,
           confirmatory, corroborative, corroboratory,
           substantiating, substantiative, validating,
           validatory, verificatory, verifying]