Back in early 1999, Peterme half-jokingly came up with "blog" as a shorter form of "weblog" and despite everyone pretty much universally disliking the word "blog" or "blogger" or "blogging" ever since, the name has stuck. I've never really liked it and lately I've taken to using the word weblog as often as possible, but I'm reminded of the very first time I used the short form of the word every single day since.
If you take a look at the top right corner image of the MetaFilter design, you'll see "Community 'blog" which is oh so quaint because when I designed the layout in May of 1999, I was pressed for space and couldn't fit "weblog" there. I even added an apostrophe to blog, because the contraction seemed so odd at the time. And yet, five years later it still remains.