“smart aleck”（亦作“smart alec”，二者拼写互通，前者为美式主流拼写，后者为变体）是英语中强贬义的名词性习语，词源可追溯至19世纪末的美国社会。相传其原型是纽约街头骗子Alec Hoag，此人以狡猾多端、自以为计划天衣无缝闻名——他屡次设计欺骗警方与市民，却因过分炫耀小聪明最终败露，其“自作聪明反被聪明误”的形象逐渐固化。1880年左右，“smart Aleck”（“smart”表“故作聪明的”，“Aleck”为“Alec”的昵称化变体）从指代具体人物的专有名词，演变为泛指“爱耍小聪明者”的固定短语，正式进入书面英语；“smart alee”则是20世纪初衍生的美式口语变体，语义与“smart aleck”完全一致，但使用频率远低于前者，考试及正式语境中以“smart aleck”为标准形式。
其核心语义是“爱炫耀浅薄小聪明、言行轻浮讨厌，且总试图显示自己比别人聪明的人，自作聪明的人”。语义关键点有三：
一是指代对象为“人”（多为单数，可指男性或女性）；
二是情感色彩纯贬义，暗含对“炫耀无深度的智慧、目中无人、爱抬杠”等行为的反感，绝非“聪明的人”（褒义）；
三是“聪明”的属性为“小聪明”——即对方的“机智”仅停留在表面，缺乏真才实学，且常伴随“打断他人、嘲笑他人、用俏皮话掩饰无知”等令人反感的行为。
固定搭配为“be such a smart aleck”。
例：
Stop being such a smart aleck—no one likes it when you interrupt the teacher to show off how much you know.
别再这么自作聪明了——没人喜欢你打断老师，就为了炫耀自己懂多少。
She broke up with him because he was always a smart aleck; every time she shared an idea, he’d mock it instead of listening.
她和他分手了，因为他总爱自作聪明——每次她分享想法，他都不认真听，反而还嘲笑她。
The politician came off as a smart aleck during the debate—he made fun of his opponent’s points rather than offering real policy solutions.
这位政客在辩论中活像个自作聪明的人——他一味嘲笑对手的观点，却提不出任何真正的政策方案。
Investors refused to trust the CEO; he sounded like a smart aleck who couldn’t back up his bold promises with actual data.
投资者不信任这位CEO——他说话像个自作聪明的人，那些大胆的承诺连一点实际数据都支撑不了。
He tried to impress his date by being a smart aleck, but she found his constant one-liners about her taste in movies annoying.
他试图靠耍小聪明打动约会对象，可她觉得他没完没了拿她的电影品味说俏皮话，特别烦人。
The teacher told the smart aleck in the back row to either ask a serious question or keep quiet during.
老师让后排那个自作聪明的学生，要么提个正经问题，要么上课就闭嘴。
When they first met, she thought he was a smart aleck—he kept correcting her pronunciation to show he spoke better English, but later she realized he was just nervous.
刚认识时，她觉得他是个自作聪明的人——总纠正她的发音，炫耀自己英语说得好，后来才发现他只是紧张。
The diplomat ignored the reporter’s smart aleck remarks about the policy; she stuck to the official statement instead of engaging in petty arguments.
这位外交官没理会记者对政策的那些自作聪明的评论，始终坚持官方口径，不参与无谓争执。
Military trainers warned that a smart aleck attitude would get soldiers in trouble—discipline matters more than showing off how clever you are.
军事教官警告说，自作聪明的态度会让士兵陷入麻烦——纪律比炫耀自己多聪明重要得多。
Her husband’s always been a bit of a smart aleck; he teases her about her cooking but never offers to help improve it.
她丈夫一直有点自作聪明——总拿她的厨艺开玩笑，却从不主动帮忙改进。
I don’t mind people being clever, but I can’t stand a smart aleck who uses their wit to make others feel stupid.
我不讨厌聪明的人，但受不了那些用小聪明让别人难堪的自作聪明者。
Ross, stop being such a smart aleck! We’re just trying to have a fun game night, not a lecture on dinosaur bones.
罗斯，别这么自作聪明了！我们只是想好好玩一晚游戏，不是来听你讲恐龙化石的。《老友记》
Leonard, you’re not being clever—you’re being a smart aleck. Sheldon’s joke was bad, but so is your need to point it out like you’re better than him.
伦纳德，你这不是聪明——你是自作聪明。谢尔顿的笑话是不好笑，但你非要指出来，搞得自己比他强似的，也很讨厌。《生活大爆炸》
Bart, if you keep acting like a smart aleck with the principal, you’ll get suspended. Learn to respect people instead of making fun of their rules.
巴特，如果你还对校长这么自作聪明，你会被停课的。学着尊重别人，别总嘲笑他们的规定。《辛普森一家》
My little brother was always a smart aleck; he’d correct every word I said and laugh when I made a mistake, which made me really angry.
我的小弟弟总是自作聪明；他会纠正我说的每一个字，当我犯错时，他会笑，这让我非常生气。（2022年全国高考）
He thought he could outsmart everyone in the team, but his smart aleck attitude made his colleagues dislike him. They all called him a "smart aleck" behind his back.
他以为自己能比团队里的每个人都聪明，但他的自作聪明的态度让同事们不喜欢他。他们都在背后称他为“聪明人”。（2023年12月四级）
Don’t be such a smart aleck! You don’t have to prove you’re clever every time we talk.
别这么自作聪明！你不必每次我们谈话都要证明你很聪明。（2025年上海中考）
