Not that it makes much difference, but "knowledge base" is a much older term than 1-2 years. The Microsoft knowledge base is the first thing that came to mind, which started in 2003. Tools like Lotus Notes were using the term before that, but I can't find exactly when.
Out of curiosity I tried to find older references. There are references using this definition back to at least 1995. Beyond that it's trickier because apparently "knowledge base" was used to describe the knowledge available to an AI system during the expert systems era, which is a somewhat different definition. e.g. Lehnert 1977: https://files.eric.ed.gov/fulltext/ED150955.pdf
This google trends graph confirms my suspicion that it was a more common term back then: https://trends.google.com/trends/explore?date=all&geo=US&q=K...
Out of curiosity I tried to find older references. There are references using this definition back to at least 1995. Beyond that it's trickier because apparently "knowledge base" was used to describe the knowledge available to an AI system during the expert systems era, which is a somewhat different definition. e.g. Lehnert 1977: https://files.eric.ed.gov/fulltext/ED150955.pdf