improve: [16] The -prove of improve has no direct connection with the verb prove, although the two have come to resemble each other over the centuries. It comes ultimately from late Latin prōde ‘advantageous’ (source of English proud). This gave Old French prou ‘profit’, which was combined in Anglo-Norman with the causative prefix em- to produce the verb emprouer. This originally meant ‘turn to a profit, turn to one’s advantage’, a sense which survives in English in one or two fossilized contexts such as ‘improve the shining hour’. Modern English ‘make or get better’ developed in the 17th century. => proud
