物

Left indexing ox radical 牜 - left-side compressed form of 牛, with the bottom-closing stroke angled up-and-out for left-side fit. Originally 物 referred to varieties of cattle (different colors, breeds); from "all kinds of beasts" the meaning generalized to "all things." Anchors 物 in the livestock family alongside 牧 (herd), 特 (special), 牲 (sacrifice).

Right 勿 supplies the sound (wù → wù, identical). 勿 itself depicts a ceremonial banner or pennant fluttering, used as a prohibition marker; here pure phonetic role. Same phonetic family: 易 (drifted), and most directly 物 itself. The phonetic match is exact, making 物 one of the cleanest phono-semantics for ox-words.