“Taper” describes how narrow the top of the crown is compared to the bottom.

用“锥形”这个词可以概括出帽顶与底部相比有多窄。

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Here's a hat that has no taper. Notice how the crown doesn't narrow as it gets to the top.

这是一个从上到下由窄变宽的帽子。注意看，它是怎样从下往上越来越窄的。

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