RSVP n. pl. RSVPs A reply to an invitation, especially an invitation that is delivered or transmitted in writing. intr.v. RSVPed, RSVP·ing, RSVPs To respond to such an invitation with a “yes” or “no.” [French R.S.V.P., formula written at the end of an invitation in order to request a reply, from r(épondez) s(‘il) v(ous) p(laît), please reply (literally, “reply, if you please”) : répondez, second person plural imperative of répondre, to answer, reply (from Old French respondre; see respond) + si, if (from Old French, from Latin s?; see so- in the Appendix of Indo-European roots) + il, he, it (from Old French, from Latin ille, that one; see al- in the Appendix of Indo-European roots) + vous, you (from Old French, from Latin v?s; see w??s in the Appendix of Indo-European roots) + plaît, third person present indicative of plaire, to please (from Old French, from Latin plac?re; see pl?k-1 in the Appendix of Indo-European roots).] American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.RSVP abbreviation for répondez s’il vous plaît [French: please reply]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014RSVP (used on an invitation to indicate that the favor of a reply is requested.) [1895?1900;