中指
なかゆび · nakayubi · JLPT N2 · noun
middle finger
🖕 中指 = nakayubi: naka (middle) + yubi (finger), so it's the finger in the middle of the hand
中 — vertical stroke 丨 through enclosure 口
Pictograph of a banner or pole piercing the center of a target or territory, depicting the idea of 'middle' or 'center'. The horizontal frame represents boundaries, and the vertical line marks the central axis. The meaning extended from spatial center to 'middle, central, China' (中国, the Middle Kingdom).
指 — hand radical 扌 + 旨 (zhǐ, phonetic)
指 is a semantic-phonetic compound. The hand radical 扌 gives the meaning — something done with the hand, namely pointing with a finger. 旨 supplies the sound 'zhǐ'. From 'finger' it naturally extended to the verb 'to point' and figurative senses like 'to indicate' or 'to refer to'.