The Collaborative International Dictionary of English v.0.48:

Legislative \Leg"is*la*tive\ (l[e^]j"[i^]s*l[asl]*t[i^]v), a.
   [Cf. F. l['e]gislatif.]
   [1913 Webster]
   1. Making, or having the power to make, a law or laws;
      lawmaking; -- distinguished from executive; as, a
      legislative act; a legislative body.
      [1913 Webster]

            The supreme legislative power of England was lodged
            in the king and great council, or what was
            afterwards called the Parliament.     --Hume.
      [1913 Webster]

   2. Of or pertaining to the making of laws; suitable to
      legislation; as, the transaction of legislative business;
      the legislative style.
      [1913 Webster]

WordNet (r) 3.0 (2006):

legislative
    adj 1: relating to a legislature or composed of members of a
           legislature; "legislative council"
    2: of or relating to or created by legislation; "legislative
       proposal"

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "legislative":
   actionable, applicable, authorized, bicameral, competent,
   congressional, constitutional, deliberative, judicial, juridical,
   just, justiciable, kosher, lawful, lawmaking, legal, legislatorial,
   legit, legitimate, licit, parliamentary, rightful, sanctioned,
   senatorial, statutory, unicameral, valid, within the law