expression, noun
taking pride in something mundane, thinking it is exceptional; Liaodong boar (literal)
A rare literary set phrase from a Chinese anecdote about a man who thought his ordinary white boar was extraordinary, only to find it was common in Liaodong. Used to mock someone who boasts about something unremarkable.
「遼東の豕」ということわざは、自分のありふれたものを自慢する愚かさを戒める。
The proverb 'Liaodong boar' warns against the foolishness of boasting about something ordinary.
From a classical Chinese story in which a man from Liaodong was proud of his white boar, unaware that such boars were common there. The exact historical origin is uncertain, but the phrase entered Japanese as a literary idiom.