na-adjective, noun
intelligent; discerning; sharp-minded
Describes a person who is mentally sharp, perceptive, and quick to understand. Often used in formal or literary contexts.
彼は明敏な頭脳の持ち主だ。
He has a sharp mind.
明敏な読者なら、その矛盾にすぐ気づくだろう。
A discerning reader would quickly notice the contradiction.