na-adjective, noun
wild; freakish; crazy; hysterical
Describes behavior, speech, or a person that is wildly eccentric, absurd, or hysterically out of control. Often used in the phrase 素っ頓狂 (そっとんきょう) for an even stronger effect.
See also: 素っ頓狂
彼は突然頓狂な声を上げて笑い出した。
He suddenly let out a wild laugh.
その頓狂なアイデアにみんな呆れた。
Everyone was taken aback by that crazy idea.
An emphatic form of 頓狂, meaning even more wildly absurd or hysterical.
The origin is uncertain. The kanji 頓 (sudden, abrupt) and 狂 (crazy, insane) are conventionally associated with the meaning of wild or freakish behavior.