noun, noun or participle which takes 'suru'
Rare literary or philosophical term for deep insight or penetrating understanding. Not used in everyday conversation; more common words like 洞察 (どうさつ) or 見識 (けんしき) are preferred.
彼の観入は問題の核心を突いていた。
His insight struck at the heart of the problem.
洞察 is the standard word for 'insight' or 'discernment' in modern Japanese, while 観入 is a rare, literary synonym.
Compound of 観 (かん, 'to observe') and 入 (にゅう, 'to enter'), suggesting 'entering through observation'. The exact historical derivation is uncertain; it appears to be a coined Sino-Japanese term.