Wikipedia definition:   "A weblog, web log or simply a blog, is a
web
application which contains periodic time-stamped posts on a common webpage."

Tuesday evening, I had a discussion on this very topic with a few luminaries of the blogging world at a dinner organized by David Teten.  People’s various definitions included the following characteristics:

– Syndication – via RSS or or similar tools
– Connectedness – This was brought forth by Ross Dawson.  He thought links are the most defining characteristic of blogs.
– Dynamism – The frequent posting of entries

I personally think the line between a "website" and a "blog" is fairly blurry.  I’d love to hear different definitions of blogs, if you come across any.