Nil

A quantity is said to be nil if it is small enough that it can be ignored. Nil is closely related to the standard mathematics concept of an infinitesimal, but it is not the same. Nil is also closely related to the concept of zero.

References

The concept of nil was brought to my attention by Harry Binswanger in his lecture Saving Math from Plato. [TODO rephrase or put this elsewhere in the document]