| 勾引 | こういん | arrest; custody; apprehending; abduction |
| 勾引状 | こういんじょう | summons; warrant of arrest |
| 勾留 | こうりゅう | detention pending trial; confinement; custody |
| 勾欄 | こうらん | railing; handrail; balustrade; armrest (chair) |
| 勾股弦 | こうこげん | three sides of right triangle (minor cathetus, major cathetus and hypotenuse) |