This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
劕 combines 質 (substance, quality) with 刂 (knife). The exact historical development and original meaning are uncertain.
The left side 質 suggests substance or quality, and the right side 刂 is a knife. Picture a knife used to test the quality of a material, but remember that the actual meaning is unclear.
For シツ, imagine a sheet of quality material being cut by the knife: sheet -> シツ, and the knife tests its substance.