TSUMUGU · TOCFL B2 (est.) · 字
副
副 ＝ 刂 ＋ 畐
ㄈㄨˋ · fù
adj/noun — secondary, deputy; (measure word) a set, a pair
字源 FORM — what the parts do
刂義a knife
畐聲fú — gives the sounda full jar, swollen with stores
Tfú → fù — only the tone shifts
A knife (刂) splits one full thing (畐) into matching parts — and the part beside the main one is the second, the deputy. 畐 fú carries the sound, only the tone falling to fù; from the split-off matching piece comes "a set, a pair": 副本、一副.
故事 STORY — a scene to remember it by
刀（刂）把那滿滿一甕（畐）分成兩份，一份留主，一份作副。
The knife (刂) divides the brimming jar (畐) into two — one kept as the main, one set aside as the second.
字源記憶法
意 · Meanings
(本義)副本、副職— secondary, a duplicate, deputy常用
→副手、副官— a second-in-command
⇒一副、全副— a set, a pair (measure word)
(本義) original meaning · → ⇒ each arrow = one more step of extension