the act of inviting.

the written or spoken form with which a person is invited.

something offered as a suggestion

an invitation to consider a business merger.

attraction or incentive; allurement.

a provocation

The speech was an invitation to rebellion.

invitational.

noun

allurement , appeal , attraction , begging , bid , bidding , call , challenge , compliments , coquetry , date , encouragement , enticement , feeler * , ground , hit , incitement , inducement , invite , lure , motive , offer , open door * , overture , paper , pass , petition , pressure , proffer , prompting , proposition , provocation , rain check , reason , request , solicitation , suggestion , summons , supplication , temptation , urge , bait , come-on , inveiglement , seduction , proposal