1The middle finger — the third finger counting from the thumb, and the longest finger of the hand.
指輪は中指にはめることが多い。
Rings are often worn on the middle finger.
彼はキーボードを打つとき、中指をよく使う。
He often uses his middle finger when typing on the keyboard.
中指を包丁で少し切ってしまった。
I accidentally cut my middle finger a little with the kitchen knife.
2The middle toe — the third toe counting from the big toe, mainly used in anatomical contexts.
足の中指をタンスの角にぶつけてしまった。
I bumped my middle toe on the corner of the dresser.