It means that the molecules or the atoms and the gas don't know about each other.

气体分子本身的体积,可以忽略不计。

麻省理工公开课 - 热力学与动力学课程节选

We're going to spend our money like crazy.

我们准备不计成本地砸钱进来。

That's all课堂 - SpeakingMax英语口语达人

So perhaps in terms of the individual badness of death that's a wash.

所以也许死亡的坏处可忽略不计了。

耶鲁公开课 - 死亡课程节选

We know there is no thing called a massless rope, but most ropes have a mass, but maybe negligible compared to the two blocks you are pulling, so we'll take the idealized limit where the mass of the rope is 0.

我们都知道无质量的绳子是不存在的,是绳子就有质量,但是相比于这两个物体就可以忽略不计了,所以我们有了这个理想的条件,即绳子的质量都是 0

耶鲁公开课 - 基础物理课程节选

Spoiler alert. And he has a standing offer, he says, "I'll pay whatever the amount is, $10,000 to the first person who can document some effect done in supernatural terms that I can't reproduce through trickery."

他给出一个长期悬赏,他说,我将不计报酬,给第一个在我面前展示,我用魔术无法再现的超自然,现象的人10000美元

耶鲁公开课 - 死亡课程节选