In the "Guangyun" (Tang Yun), pronounced "ju" (entering tone), it is formed by the fanqie of "qu" and "zhu". In the "Jiyun" (Jiyun), it is formed by the fanqie of "jiu" and "xu", pronounced the same as "ju". "Shuowen Jiezi" (Shuowen Jiezi) explains it as swollen gums. Also, the "Jiyun" (Jiyun) records that loose teeth are called "ju". Also, in the "Jiyun" (Jiyun), it is formed by the fanqie of "gou" and "xu", pronounced the same as "ju". It is also formed by the fanqie of "ke" and "yu", pronounced the same as "ju". The meanings are the same.