오리무중

Etymology
, from a discussion in the Chinese history  about the Daoist master (c. 80—c. 149), who was said to possess the supernatural ability to summon such a mist.

Noun

 * 1)  being up in the air; a very uncertain and unclear situation
 * 2)  a deep fog
 * 1)  a deep fog
 * 1)  a deep fog
 * 1)  a deep fog
 * 1)  a deep fog