noun, noun or participle which takes 'suru', intransitive verb
farewell to those staying behind
A formal, literary term for saying goodbye to people who remain when one departs. Not used in everyday conversation; modern Japanese would typically use 別れの挨拶 or similar phrases.
彼は旅立つ前に、留別の宴を開いた。
Before setting off on his journey, he held a farewell banquet for those staying behind.
Compound of 留 (to stay, remain) and 別 (parting, separation). The exact historical derivation is uncertain; the spelling is conventionally associated with the meaning of bidding farewell to those who stay.