verb, RSVPed or RSVP'd, RSVPing or RSVP'ing, noun, plural RSVP's.| 1. | to reply to an invitation: Don't forget to RSVP before Thursday. |
| 2. | a reply to an invitation: He sent a lovely bouquet of flowers with his RSVP. |
| 3. | (used on an invitation to indicate that the favor of a reply is requested). |
