The oracle-bone scribes drew a mouth caught mid-speech, with a forked tip rising from inside it — the tongue itself, sometimes flanked by small drops for the saliva of talking. 舌 is what lives inside 口 (mouth) and makes speech possible: without it, sound has no shape. Later scribes straightened the fork into the two short strokes that still crown today's character.
A piece of culture
A tongue worth an army In 257 BCE, a minor aide named Mao Sui talked his way into a desperate diplomatic mission, then argued the king of Chu into an alliance with nothing but words — no army, no gold. His lord, Lord Pingyuan, praised him with a line still quoted today: "Mr. Mao's three-inch tongue is stronger than a million-man army." The idiom born from it, 三寸不烂之舌 — "a three-inch tongue that never rots" — still describes someone whose words alone can win the day.
Use it in a real word
口舌
kǒushé · hau2 sit3
verbal trouble, or eloquence — literally "mouth and tongue"; you already know 口