域いき

noun

region; limits; stage; level

Used for a bounded area, range, or degree. Often appears in compounds or set phrases like 域を出ない (does not go beyond a certain level) or 域に達する (reaches a certain stage).

• 彼かれの実じつ力りょくはまだその域いきに達たっしていない。

  His ability hasn't reached that level yet.

• この問もん題だいは専せん門もん家かの域いきに属ぞくする。

  This problem belongs to the domain of experts.