Top indexing radical
小 (Kangxi #42) - three strokes meaning 'small.' Sits above
土 (earth) to give a transparent ideograph: small + earth = tiny grains of dust. Same radical anchors
少,
尔. The PRC simplified
尘 from traditional
塵 (deer-over-earth, kicked-up dust); the modern form is a clean compound ideograph crafted in 1956.