家喻户晓 — “Universally known”

The idiom "家喻户晓" originates from an event recorded in "Lie Nü Zhuan" (Biographies of Exemplary Women), compiled during the Han Dynasty.

It tells the story of a woman named Liang Gu. One day, her house accidentally caught fire. Inside were her brother's child and her own two children. She bravely rushed into the burning house, intending to rescue her brother's child first. However, when she emerged, it was one of her own children.

By then, the fire had become too fierce to re-enter. Distraught, she stamped her feet and cried bitterly, exclaiming, "How can this be? Won't I be accused of selfishness? How can the Liang family be '户告人晓' (known to every household and person) for such a deed, letting people curse me? How will I ever face anyone again?" With these words, she disregarded her own safety and plunged back into the inferno, ultimately perishing in the flames.

In this context, '户告人晓' meant 'every household spreading the word, everyone knowing.' Later, it was written as '家至户晓,' meaning 'reaching every household, known by every household.' Gradually, it evolved into its present form, '家喻户晓.'