脱口而出

1. Basic Information

• Pinyin: tuō kǒu ér chū
• English Translation: To blurt out / To roll off the tongue
• Idiom Composition: 「脱」（To escape or shed; here, it refers to words "escaping" the mouth.）＋「口」（Mouth.）＋「而」（A conjunction connecting the action to the result.）＋「出」（To come out or exit.）
• Meaning: To speak spontaneously without prior thought, either due to a sudden impulse, deep familiarity with a subject, or a lack of self-control.

2. Detailed Meaning and Nuances

「脱口而出」 contains the following nuances:

• Reflexive Response: Refers to the state where words bypass the mental filter and are spoken as a reflex, often triggered by intense external stimuli.
• Fluency and Mastery: In a positive sense, it describes a level of proficiency where knowledge is so deeply internalized that it can be recited or applied without hesitation.
• Careless Speech: It can also describe a lack of discretion, where one speaks too quickly and reveals private information or unfiltered thoughts.

3. Usage

「脱口而出」 is mainly used in the following contexts:

• Emotional Outbursts: Used when words are spoken reflexively due to strong emotions like surprise, joy, or anger.
  • Example:「看到那惊人的魔术表演，他不禁脱口而出：“太不可思议了！”」
    （Seeing that amazing magic trick, he couldn't help but blurt out, "That's incredible!")
• Mastery and Fluency: Used as a compliment to describe someone so well-versed in a topic that the right words come out naturally and effortlessly.
  • Example:「他对唐诗烂熟于心，随便一句都能脱口而出。」
    （He knows Tang poetry so well that any line will roll off his tongue effortlessly.)
• Slips of the Tongue: Used in a negative context when someone accidentally reveals a secret or says something they should have kept to themselves.
  • Example:「虽然我想保密，但那个名字还是差点脱口而出。」
    （Although I wanted to keep it a secret, that name almost slipped out.)

Additional Examples:

1. 答案就在嘴边，他想都没想就脱口而出。
   （The answer was on the tip of his tongue, and he blurted it out without even thinking.）
2. 伤人的话一旦脱口而出，就再也收不回来了。
   （Once hurtful words slip out, they can never be taken back.）
3. 听到这个好消息，大家都不约而同地脱口而出：“万岁！”
   （Hearing the good news, everyone shouted out "Hooray!" in unison.）
4. 因为太紧张，他把心里话脱口而出了。
   （Because he was so nervous, he accidentally let slip what he was really thinking.）

4. Cultural Background and Notes

• Wide Usage: This idiom is extremely common in both daily conversation and literature to describe the physical act of speaking without hesitation.
• Neutrality: Unlike some idioms that are strictly positive or negative, 脱口而出 (tuō kǒu ér chū) is neutral. Its meaning depends entirely on whether the 'blurting' was a sign of honesty, brilliance, or recklessness.
• Comparison: A similar phrase is 冲口而出 (chōng kǒu ér chū), which implies a more forceful or aggressive 'bursting out' of words, often driven by intense, uncontrollable emotion.

5. Similar and Opposite Idioms

• Similar Idioms:
  • 不假思索 (bù jiǎ sī suǒ): To act or speak immediately without the need for thinking.link
  • 心直口快 (xīn zhí kǒu kuài): To be frank and outspoken; saying exactly what is on one's mind.
  • 毫不犹豫 (háo bù yóu yù): To not hesitate at all.link
• Opposite Idioms:
  • 守口如瓶 (shǒu kǒu rú píng): To keep one's mouth shut like a bottle; to be extremely tight-lipped about secrets.
  • 三思而行 (sān sī ér xíng): To think three times before acting; to be cautious and deliberate in speech and action.
  • 三思而后行 (sān sī ér hòu xíng): Think thrice before you act.link
  • 一言不发 (yī yán bù fā): Not saying a single word.link

6. Summary

The idiom 脱口而出 (tuō kǒu ér chū) literally describes words "escaping the mouth." It is a versatile expression used to describe speech that happens without a mental filter. Depending on the context, it can signify a spontaneous emotional outburst, the impressive fluency of a scholar, or a careless slip of the tongue that reveals a secret.