morning suit
noun [ C ] uk/ˈmɔː.nɪŋ ˌdres/ us/ˈmɔːr.nɪŋ ˌdres/ (UK also morning dress [ U ])
晨礼服,常礼服(在婚礼等场合穿用,包括黑色或灰色外套、条纹长裤及大礼帽)
a very formal set of clothes worn by some men on occasions such as marriage ceremonies, including a long black or grey coat, striped trousers, and a top hat