大だい親しん友ゆうだいしんゆうMeanings1nounbest friend; very close friendEmphatic term for a best friend or extremely close friend, stronger than 親友 alone. Often used by younger speakers.彼かの女じょは私わたしの大だい親しん友ゆうです。She is my best friend.大だい親しん友ゆうと一いっ緒しょに旅りょ行こうに行いった。I went on a trip with my very close friend.