early 15c., from Old French concave (14c.) or directly from Latin concavus "hollow, arched, vaulted, curved," from com-, intensive prefix (see com-), + cavus "hollow" (see cave (n.)).
实用例句
1. The palm of one's hand is slightly concave.
人的手掌是微凹的.来自《现代汉英综合大词典》
2. The graph of a concave function is always below its tangent.
一个凹函数的图象总在它的切线的下方.来自辞典例句
3. The cloven hooves are sharp edged , elastic and concave.
蹄锋利,呈凹形, 富有弹性.来自辞典例句
4. Alternative characterization of concave and convex functions which is sometimes useful.
对于凹函数和凸函数还有一个替补的表征,有时它是有用的.来自辞典例句
5. In adults its contour may be straight, slightly concave or slightly convex.
