Chinese idiom · 成语
夜郎自大
Meaning
Yelang thinks itself great; to be arrogant from ignorance.
Character by character
夜郎Yelang (ancient kingdom)
自self
大great, big
Origin and story
From Records of the Grand Historian (Shǐ jì). The small Yelang kingdom boasted of its might, unaware of Han’s vastness.