TSUMUGU · TOCFL B2 (est.) · 字
臂
臂 ＝ 月 ＋ 辟
ㄅㄧˋ · bì
noun — the arm (手臂、臂膀)
字源 FORM — what the parts do
辟聲bì — gives the sounda body and a knife dividing off a space
Flesh (月, the body radical) under 辟 bì, which carries the exact sound. The limb of flesh that splits off the shoulder and reaches out — the arm. The same 辟 builds 壁、避、璧, all read bì.
故事 STORY — a scene to remember it by
從肩頭分出（辟）的一條肉（月），伸出去拿東西。
A length of flesh (月) branching off the shoulder (辟), reaching out to take hold.
字源記憶法
意 · Meanings
(本義)手臂、臂膀— the arm常用
→助一臂之力— to lend a hand — an arm's worth of help
(本義) original meaning · → ⇒ each arrow = one more step of extension
關 · Related
壁＝ 土 ＋ bìthe series — 壁 sets on earth (土) for the wall; 臂 sets it on flesh () for the arm辟pìthe sound donor — the dividing knife it lends, read bì in this series