夜郎自大 やろうじだい Meanings Noun, な-adjective throwing one's weight around without knowing one's limitations (literally: Yelang thinks too highly of itself) Kanji 夜 night. Read as ヤ. 郎 son. Read as ロウ. 自 self 大 big. Read as ダイ. Word lists Yojijukugo (四字熟語) Jinuma: Japanese Dictionary · Word lists