サツ, サイ, セツ, ころ.す, ごろ.し, そ.ぐ
kill, murder, butcher, slice off, split, diminish, reduce, spoil
JLPT3 G4 S10 F581
The relevant seal inscription form is 乂# (vegetation cut in swaths) + an element combining millet and 殳 action indicator → harvest ears of millet and *scrape* them for their seeds → *shave*; *erase*. The primary meaning, however, is now *kill*, via the conceptual progression from "harvest" to "action that cuts off life." Compare 絶.
[Full Kanji Etymology List]