affirm
     v 1: establish or strengthen as with new evidence or facts; "his
          story confirmed my doubts"; "The evidence supports the
          defendant" [syn: {confirm}, {corroborate}, {sustain}, {substantiate},
           {support}] [ant: {negate}]
     2: to declare or affirm solemnly and formally as true; "Before
        God I swear I am innocent" [syn: {verify}, {assert}, {avow},
         {aver}, {swan}, {swear}]
     3: say yes to
Source: WordNet® 2.0