RSVP
uk/ˌɑː.res.viːˈpiː/ us/ˌɑːr.es.viːˈpiː/
（请柬用语）敬请赐复（法语répondez s’il vous plaît的缩写）
abbreviation for "répondez s’il vous plaît", French for "please reply"; used at the end of a written invitation to mean that you should let the people who invited you know whether or not you are coming
RSVP by 9 October. 请于10月9日前赐复。
RSVP
verb [ I ] informal uk/ˌɑː.res.viːˈpiː/ us/ˌɑːr.es-/
回覆请柬，确认是否参加
to answer an invitation saying whether or not you will attend
I got a party invitation in the post, and I called to RSVP. 我收到一封聚会邀请信，已经打电话确认会参加了。