The Collaborative International Dictionary of English v.0.48:

Legitimate \Le*git"i*mate\ (-m[=a]t), v. t. [imp. & p. p.
   Legitimated (-m[=a]`t[e^]d); p. pr. & vb. n. Legitimating
   (-m[=a]`t[i^]ng).]
   To make legitimate, lawful, or valid; esp., to put in the
   position or state of a legitimate person before the law, by
   legal means; as, to legitimate a bastard child.
   [1913 Webster]

         To enact a statute of that which he dares not seem to
         approve, even to legitimate vice.        --Milton.
   [1913 Webster]