This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
劗 combines 贊 (left) and 刂 (knife). The exact historical development is uncertain, but it likely relates to cutting or reducing, as suggested by the knife radical and its readings.
The left side 贊 suggests something valuable or praised, and the right side 刂 is a knife. Imagine a knife cutting away excess to reveal something valuable, hinting at reducing or cutting.
For サン, imagine a knife cutting a sandwich: sandwich -> サン, and the knife 刂 slices it.