Pictograph: two people standing back-to-back. The encoded reasoning: in ancient Chinese court tradition, emperors sat facing south (the warm, sunny direction); their BACKS were toward north. So 北 = "the back-to-back direction" = north. The character also retains a secondary meaning of "to flee / turn one's back" — preserved in the compound 敗北 (defeat — "to be defeated and turn one's back / flee"). Identical across 繁體 / 新字体 / 简体.

The back-to-back etymology is one of the most directly anatomical in the script. The character 背 (back of body, from earlier batch) actually contains 北 + 月 (flesh) — encoding "the back-of-body" by adding flesh to the back-to-back picture. Both characters preserve the same cultural geometry.

Mandarin: běi, dipping 3rd tone. 北方 (běifāng, the North), 北京 (Běijīng, Beijing — "Northern Capital", China's capital), 东北 (Dōngběi, Northeast — Manchuria region), 北部 (běibù, northern part), 北方人 (běifāng rén, northerner). Beijing's name literally translates to "Northern Capital" — paired with Nanjing 南京 ("Southern Capital").

Korean has two pronunciations of this character — preserved from classical Chinese: — (buk): north. Used in 北方 (북방), 北韓 (북한, North Korea), etc. — (bae): to flee / be defeated. Survives only in 敗北 (패배, defeat).

Japanese: on-reading ホク (hoku) for compounds — 北極 (Hokkyoku, North Pole), 北海道 (Hokkaidō, Hokkaido — Japan's northernmost prefecture, "Northern Sea Road"), 東北 (Tōhoku, Tohoku region — northeast Japan), 北部 (hokubu, northern part). Kun-reading きた (kita) is the everyday word — 北 (kita, north), 北口 (kitaguchi, north exit), 北風 (kitakaze, north wind).

Memory aid: two people back-to-back, facing opposite ways. The back side of the south-facing emperor.