家jiā喻yù户hù晓xiǎo

Literal: understood in every family, known in every household
Figurative: So well known there is not a household that hasn't heard of it: a person, a story, or a brand that everybody recognizes.

Where does 家喻户晓 come from?

It does not come from a particular story: it is a formula built on parallelism, with two pairs that say much the same thing — 家 ("family") with 喻 ("to grasp") and 户 ("household") with 晓 ("to know"). The doubling is what conveys that the news has reached every last corner. It tends to go with names, works, and characters, and it carries a note of admiration, though it works just as well for things that are famous without deserving it.

How is 家喻户晓 used? Two examples

这zhè个ge牌pái子zi在zài国guó内nèi家jiā喻yù户hù晓xiǎo，但dàn在zài国guó外wài没méi什shén么me人rén知zhī道dào。
This brand is a household name back home, but hardly anyone abroad has heard of it.
他tā因yīn为wèi那nà部bù电diàn视shì剧jù一yī夜yè之zhī间jiān家jiā喻yù户hù晓xiǎo。
That TV series made him a household name overnight.

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