邮编
yoú biān · HSK 7
postal code
📮 邮编 = 邮 mail/post + 编 to arrange-into-a-number; the post office number for a place
邮 is the mail/postal character (also in 邮票 stamp, 邮件 mail). 编 means to arrange, weave, or assign a number (as in 编号 serial number). Together: the number assigned to a postal area, a zip code.
邮 — 由 (cause) + 阝 (city radical 邑)
邮 means 'post, mail.' The right-side 阝 derives from 邑 (city/settlement), pointing to relay stations along roads. The simplified form pairs this with 由, which here mainly carries the sound. Historically 邮 referred to the courier posts where messengers changed horses to relay official messages.
编 — silk radical 纟 + flat 扁
A semantic-phonetic compound. The silk radical 纟 signals the original meaning: weaving or plaiting cords and threads. The right side 扁 (biǎn) supplies the sound. From 'to weave/plait' the meaning extended to arranging things in order, hence 'to compile, edit, or organize.'