a spoken or written request to somebody to do something or to go somewhere

the act of inviting somebody or of being invited

He produced an official letter of invitation.

Admission is by invitation only.

A concert was held at the invitation of the mayor.

a card or piece of paper that you use to invite somebody to something

We've already sent out the invitations.

Have you ordered the wedding invitations yet?

something that encourages somebody to do something or encourages something to happen, usually something bad

Leaving the doors unlocked is an open invitation to burglars.

Putting the kids in charge was an invitation to disaster.

LEARNit Dictionary