These words all change meaning over time, mathematical definitions change, old words are used to describe new objects and new words are used to describe old objects. I'm using the word integer with it's archaic meaning here for rhetorical effect, but I'm probably being too obtuse ;)

To clarify, we used to think of integers as just the natural numbers. Integer was a colloquial word meaning "whole, entire", so there was presumably a discussion about how negative numbers were whole or entire, though I vaguely remember this historical story. My point is just that at some point negative numbers were seen as a advanced extension of the natural numbers. Even zero was seen as an unnatural extension, which is why there is a confusion to this date as to whether "natural" numbers include zero.

ref: http://mathforum.org/library/drmath/view/57212.html

Not the best reference, but I've read it elsewhere, so maybe it's a myth, but someone can trace it to the source if they want.

> We don't call them "real" numbers outside of math circles anymore.

I mean laypeople don't know what the real numbers are in distinction to the rationals, for example.