The name stems from the waveform's appearance on a scope; it looks like the teeth of a hand saw.

锯齿波的名字来源于示波器上其波形的形状，它看上去就像是手锯的齿一样。

youdao

But, if less idealised, it is a lot more human and exhibits one very human characteristic in particular: he might have been the Lord of all he saw, but young King Tut had buck teeth.

然而即便没有那般理想，它却更具人性，展现出人类的突出特点：或许他曾是万物之尊，但年轻的图坦卡蒙法老的确长着龅牙。

youdao

The sharp parts of a comb or a saw are called teeth.

梳子和锯子的尖锐部分叫作齿。

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One-year forecasts are pretty much worthless (witness the past year, which saw stocks zoom into the teeth of a weak, slow recovery), and even decade-out estimates are close to garbage.

FORBES: Serious Investors Will Ignore the Fiscal Cliff