📖 Meaning
Like a louse in one's mouth — a metaphor for an enemy so weak and exposed that it can be destroyed effortlessly. It describes a foe entirely at one's mercy, with no means of escape or resistance.
📜 Origin Story
The phrase originates from the Warring States period text Han Feizi (《韩非子·七术》), written by the Legalist philosopher Han Fei. In the passage, Han Fei advises a ruler that by advancing upon Dongyang, the strategic city of Handan would become as trivial to seize as a louse caught in one's mouth — utterly defenseless and easy to crush. The metaphor was later echoed in the Book of Han (《汉书·王莽传》), where a military officer compared swallowing the northern barbarians to plucking lice from one's mouth, so trivial was their strength relative to the Xin dynasty's might.
💡 Example Usage
敌军粮草断绝，已成口中蚤虱，覆灭只在旦夕之间。
With their supply lines severed, the enemy forces are like lice in the mouth—their annihilation is only a matter of days.
🏷️ Category
➕ Similar Idioms
➖ Opposite Idioms
🔤 Quick Facts
- Chinese: 口中蚤虱
- Pinyin: kǒu zhōng zǎo shī
- Literal Translation: in, mouth, flea, louse
- Category: Power
- Characters: 4