偏へん狂きょう

na-adjective, noun

monomania; monomaniac

A somewhat literary or technical term for an obsessive fixation on a single idea or subject. Can refer to the condition or a person with it.

• 彼かれは偏へん狂きょう的てきなまでに切きっ手て収しゅう集しゅうに没ぼっ頭とうしている。

  He is obsessed with stamp collecting to the point of monomania.

• その発はつ明めい家かは偏へん狂きょうと言いわれるほど一ひとつの研けん究きゅうに打うち込こんだ。

  The inventor devoted himself to a single line of research to the extent that he was called a monomaniac.