Whence and co.

While none of these posts will contain original content (I am after all, mostly copying out of dictionaries etymologies that I happen to find interesting, elaborating and synthesizing a bit) this one is a particularly bad example. The only thing I have to add to this is a nicely formatted chart showing a regularity in these fun words (some archaic but some definitely still current) which I had never before suspected:

whence	hence	thence
where	here	there
whither	hither	thither
wherefore	herefore	therefore
wherein	herein	therein

I didn't realize that herefore was a word, but it makes sense.

Of course, there are irregulars: while what and that follow the form we use this instead of "hat," and although which follows the wh- form for an interrogative we don't have "thich or "hich."