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convex + noun
convex 作定语时常用以修饰 lens、mirror、polygon、set 等名词。
A convex lens focuses light.
凸透镜能聚焦光线。
凸的；鼓起的
先理解核心含义，再看它在真实句子里的用法。
凸的；鼓起的
curving or bulging outward
A convex lens focuses light.
凸透镜能聚焦光线。
像碗、圆或球的外表面那样向外弯曲的；凸的。
Curved or bowed outward like the outside of a bowl, circle, or sphere.
向外凸起的
curving or bulging outward
上境图是凸集的。
having an epigraph that is a convex set.
没有内角大于180度的。
having no internal angles greater than 180 degrees.
The convex mirror on the wall allows the driver to see a wider area.
墙上的凸面镜让司机能看到更广的区域。
The lens of a magnifying glass is convex on both sides.
放大镜的镜片两面都是凸起的。
In geometry, a convex polygon has all interior angles less than 180 degrees.
在几何学中，凸多边形的所有内角都小于180度。
convex 作定语时常用以修饰 lens、mirror、polygon、set 等名词。
A convex lens focuses light.
凸透镜能聚焦光线。
be 后接 convex 表示状态，可用 slightly、strongly 等程度副词修饰。
The surface of the shield is slightly convex.
盾牌的表面略微向外凸起。
become 后接 convex 表示从非凸状态变为凸的状态。
The metal plate became convex after heating.
金属板加热后变得向外凸起。
Not this
The convex of the lens helps focus light.
Use this
The convexity of the lens helps focus light.
convex 是形容词，不能直接作名词；表示“凸状、凸面”时要用名词 convexity。改正后句子结构完整，意思不变。
Not this
After the collision, the panel had a convex dent.
Use this
After the collision, the panel had a concave dent.
dent 指“凹痕、凹陷”，语义是向内凹；convex 表示“向外凸”，两者矛盾。concave 才表示“向内凹”，能与 dent 搭配。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
凸透镜
A convex lens focuses light to a point.
凸透镜将光聚焦到一点。
凸面镜
The convex mirror shows a wider area behind the car.
凸面镜显示车后更宽的区域。
凸包
The convex hull of a set of points is the smallest convex polygon containing them.
一组点的凸包是包含它们的最小凸多边形。
凸面
The convex surface of the shield deflected the arrow.
盾牌的凸面使箭偏离了方向。
凸形
The bowl has a convex shape on the outside.
这只碗的外形是凸的。
凸侧
The curve bends toward the convex side.
曲线向凸侧弯曲。
Use convex naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
联想凸透镜：中间向外鼓的镜片就是 convex。词形里字母 v 像向外张开的尖角，记住 v 朝外 = 凸。
语域：mixed 常见场景：mathematics、optics、describing shapes convex 在数学（如 convex set、convex function）和光学（如 convex lens）中属正式术语，多用于教材或专业文章；日常描述物体向外弯曲或鼓起的形状时语气中性，也可用 curved outward 等更口语的说法。
形容词，通常用作定语或表语，不依赖特定介词。
Dictionary facts from AI_FALLBACK, ECDICT, WIKTIONARY.