adj.凹的

n.凹面；凹線；凹形

The palm of one's hand is slightly concave. 人的手掌是微凹的。

A cylinder is a hollow tube with a closed concave base that permits it to stand upright. 鋼瓶是中空的管道，封閉的底部是凹入的，這樣可以直立起來。

His figure looks very funny in the concave mirror. 他的樣子在凹鏡里顯得非常可笑。

These are aberration-corrected holographic concave gratings. 下表所列為像差校正全息凹面光柵。

The cloven hooves are sharp edged, elastic and concave. 蹄鋒利，呈凹形，富有彈性。

adj.平凹的

adj.兩面凹的