Wu Collection, Lower Volume Radical: Cave (xué) 窬 Kangxi strokes: 14 Page 867, Entry 01 Pronounced yu. Shuowen Jiezi (Dictionary of Graphic Components): To cut a hole in a wooden door. Also defined as being empty inside. Also refers to carving a board to serve as a door. Guangyun (Broad Rhymes): A small hole at the side of a door. Book of Rites (Liji): A door made of brambles and a small aperture shaped like a jade tablet. Annotation: A small door beside a main door, made by piercing a wall, shaped like a jade tablet. Analects (Lunyu): Thieves who bore through walls and dig under doors. Annotation: Refers to digging a hole through a wall. Also pronounced tou. Same meaning. Also pronounced dou. Same meaning. Also pronounced dou. Refers to low-lying or deep-set terrain. Also Zihui Bu (Supplement to the Collection of Characters): A vessel used for urine and excrement. Meng Kang states: A toilet utensil.