續一切經音義 9.26

9.26

跟趺（上古痕反切韻云足後跟也下方無反玉篇脚趺也謂脚面也說文又從付作跗也）。

跟趺 (The upper character is 古 + 痕 with fanqie. The Qieyun says: 'The heel at the back of the foot.' The lower character is 方 + 無 with fanqie. The Yupian says: 'The instep of the foot; it refers to the dorsal surface of the foot.' The Shuowen also writes it with 付 as 跗).