- pur-
[pur- 词源字典]
- Middle English and Anglo-French perfective prefix, corresponding to Old French por-, pur- (Modern French pour), from Vulgar Latin *por-, variation of Latin pro- "before, for" (see pro-). This is the earliest form of the prefix in English, and it is retained in some words, but in many others it has reverted to Latinate pro-.[pur- etymology, pur- origin, 英语词源]