invitational

from WordNet (r) 3.0 (2006)

invitational
    adj 1: pertaining to or characteristic of an invitation

from The Collaborative International Dictionary of English v.0.48

invitational \invitational\ adj.
   open only to persons issued an invitation; -- of gatherings,
   usually sports events; as, an invitational tournament.

   Syn: invitation(prenominal).
        [WordNet 1.5]