Japanese edit

Kanji in this term
どう
Grade: S
こう
Grade: S
かつ
Grade: S
やく
Grade: 4
きん
Grade: 6
kan’yōon kan’on
 瞳孔括約筋 on Japanese Wikipedia

Etymology edit

瞳孔 (pupil) +‎ 括約筋 (sphincter), calque of New Latin sphinctēr pūpillae

Noun edit

(どう)(こう)(かつ)(やく)(きん) (dōkō katsuyakukin

  1. a pupillary sphincter