I think the person who created the page just posted some quick terms without defining them. It's a perfectly valid term, although I would personally change it to Chain Branch. It's not a very complex term, but I'm having a hard time thinking of how to succinctly define it off the top of my head. I don't have time to work on it at the moment, but here is a sentence that I wrote while I was trying to think of how to lead in to defining it. I hadn't gotten to the chain branch part of the definition yet. This definition is somewhat descriptive of the term Proof-of-Work, which is another term that should be added. There are plenty more definitions which haven't been included yet. I'll add some more at some point when I've got some time and if I don't forget.
Edit: It just occurred to me that the Bitcoin difficulty increases at much smaller increments than x2. Bitcoin doesn't attempt to only get consecutive zeros, but tries to get the hash below a certain number when the hash is expressed as a number.