長 is a side-view pictograph of an elderly person — long flowing hair, a slightly bent posture, leaning on a staff. From oracle bone times the silhouette has been clear: this is not just a long object but a person whose long hair signals age, and whose age signals authority. The character's extraordinary semantic span unfolded from this single image: long hair → long-lived → elder → leader. One character, three semantic clusters: length (physical), duration (time), and rank (social).

Korean reading "jang." This single character anchors nearly every Korean word for "leader / head of an organization": 校長 (gyojang, school principal), 會長 (hoejang, chairman / president of an association), 社長 (sajang, company president — though Korea uses 사장 native-feeling), 部長 (bujang, department head), 議長 (uijang, speaker / chairperson). Plus the length/time meanings: 長短 (jangdan, "long-short" = pros and cons / the gist), 成長 (seongjang, growth), 身長 (sinjang, body height), 延長 (yeonjang, extension). All three semantic threads — physical length, temporal duration, hierarchical rank — are equally alive in modern Korean.

Mandarin is one of the cleanest examples in the entire CJK system of a 破音字 (tone-shifting character). cháng, 2nd tone = "long" (physical length, duration): 长度 (chángdù, length), 长城 (Chángchéng, the Great Wall — literally "Long Wall"), 长江 (Chángjiāng, the Yangtze River). zhǎng, 3rd tone = "to grow / be elder / leader": 长大 (zhǎngdà, to grow up), 校长 (xiàozhǎng, school principal), 部长 (bùzhǎng, department head). Same character (or simplified 长), tones distinguish meaning. Korean and Japanese students who learn Mandarin frequently miss this tone-split because their own languages use a single reading.

Japanese on-reading チョウ (chō) — 校長 (kōchō, school principal), 会長 (kaichō, chairman), 身長 (shinchō, body height), 成長 (seichō, growth), 社長 (shachō, company president — used constantly in Japanese business contexts). Kun-reading ながい (nagai, "long") — 長い (nagai), 長さ (nagasa, length). One word ながい covers physical length and time duration without tonal differentiation. The phrase 長い間 (nagai aida, "long time") is one of the highest-frequency time expressions in Japanese.

Memory aid: an elderly person with long flowing hair leaning on a staff — long hair, long life, long authority. One character, three meanings unfolding from one picture.