毫háo不bù犹yóu豫yù

Literal: without a hair of hesitation
Figurative: To act without the slightest hesitation or a moment's doubt; the opposite of 犹豫不决, it describes a quick, firm decision.

Where does 毫不犹豫 come from?

It does not come from any story; the phrase is built transparently. 毫 is the finest hair on an animal, hence "a trace, the least bit"; 毫不 before a verb means "not in the least," the same pattern as 毫不在乎 or 毫不客气. 犹豫 means "to hesitate, to waver." It is usually an adverb, followed by 地 (毫不犹豫地答应), describing a decision made on the spot, whether generous, brave or blunt. It is the exact reverse of 犹豫不决, which describes someone who cannot make up their mind.

How is 毫不犹豫 used? Two examples

朋péng友you找zhǎo我wǒ借jiè钱qián救jiù急jí，我wǒ毫háo不bù犹yóu豫yù地de转zhuǎn给gěi了le他tā。
A friend asked to borrow money for an emergency, and I sent it to him without a second thought.
公gōng司sī招zhāo人rén去qù海hǎi外wài，别bié人rén还hái在zài犹yóu豫yù不bù决jué，他tā已yǐ经jīng毫háo不bù犹yóu豫yù地de报bào了le名míng。
The company was looking for people to go overseas; while the others were still dithering, he had already signed up without a moment's hesitation.

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