This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 剘 is uncertain. It visually combines 其 and 刂, but the original semantic or phonetic role of these components is unclear.
The left side 其 suggests a basket or winnowing fan, and the right side 刂 is a knife. Imagine cutting or trimming a basket, but the exact meaning is unclear.
For キ, picture a key (キ) being used to cut the basket: key -> キ.