noun
fictitious person; imaginary person
Literary term from classical Chinese, used to refer to a hypothetical or made-up person, often in philosophical or rhetorical contexts. Rare in modern Japanese.
「烏有先生」は、中国の古典に登場する架空の人物の名である。
"Uyū-sensei" is the name of a fictitious person appearing in classical Chinese literature.
架空 is a common adjective meaning 'fictional' or 'imaginary', while 烏有先生 is a rare, specific literary term for a fictitious person.
From classical Chinese 烏有先生 (wūyǒu xiānshēng), literally 'Mr. Nothing' or 'Master Nonexistent', used as a name for a hypothetical person in ancient texts. The exact historical derivation is uncertain beyond its literary origin.