How Well Do You Know English Slang?
1630s, from un- (1) "not" + past participle of invite (v.).
1530s, a back-formation from invitation, or else from Middle French inviter (5c.), from Latin invitare. As a noun variant of invitation it is attested from 1650s. Related: Invited; inviting.
1650s, from invite (v.).
An invitation: You can't go in there without an invite (1615+)