一切經音義 6.236

6.236

測度（上楚力反鄭玄注周禮云測猶度也不知廣深曰測說文從水則聲也下徒洛反）。

測度 (estimating and measuring: the first character is [pronounced with the fanqie] 楚力. Zheng Xuan's commentary to the Rites of Zhou says: 'Cè (測) is like measuring; finding out an unknown breadth or depth is called cè.' The Shuowen jiezi says: 'It derives from 水 with 則 as phonetic.' The second character is [pronounced with the fanqie] 徒洛.)