The inside or interior surface/side of something; the inward-facing part not visible from outside.
この箱の内面には防水シートが貼ってある。
The interior of this box is lined with a waterproof sheet.
鏡の内面を丁寧に拭いて曇りを取った。
I carefully wiped the inside surface of the mirror to remove the fog.
器の内面にひび割れが見つかった。
A crack was found on the inside of the vessel.
One's inner self; the mind, emotions, or inner character not shown outwardly.
彼女の内面は穏やかで、表情からは分かりにくい。
Her inner nature is calm and is hard to tell from her expression.
小説は登場人物の内面描写がとても深い。
The novel has very deep portrayals of the characters' inner lives.
自分の内面と向き合う時間が必要だと感じた。
I felt I needed time to face my inner self.