内肛門括約筋 ないこうもんかつやくきん Meanings Noun internal anal sphincter (muscle) Kanji 内 inside. Read as ナイ. 肛 anus. Read as コウ. 門 gate. Read as モン. 括 tie up. Read as カツ. 約 promise. Read as ヤク. 筋 muscle. Read as キン. Word lists Anatomy Jinuma: Japanese Dictionary · Word lists