サ, さ.す, さ.し
distinction, difference, variation, discrepancy, margin, balance
JLPT3 G4 S10 F449
The relevant bronzeware inscription form combines 左# (aligned at an angle) + a rice plant → rice plants in irregular alignment → *inconsistent*; *difference* (← irregular) → *dispatch* (← send forth ← protrude) → *thrust*; *offer* (← dispatch). The verb さす bears many extended senses from the idea of "thrust," including *extend*; *stretch*; *insert*; *raise* (the hands); *put up*; *carry*; *hold*; and *wear*.
[Full Kanji Etymology List]