I strongly disagree. It is not semantic at all. Difference between a browser and a web rendering engine is huge. I am in a business of building a browser and although we get rendering engine for free, three years later and thousands of dev hours later, our browser is still in beta and half finished. [1]
Building a general purpose web browser is one of the most challanging software development projects. This may not be the case if one is cloning Chromium/Firefox where you get both the rendering angine and the browser app for free. If you are using WebKit, you are writing the browser application from scratch.