Alright, I bow down to you for I am a fool.
But I'm not trying to be a smart*** here, but it's very commonly referred to as the "Big Bang" and bangs are quite generally associated with explosions, and are usually also associated with a very loud sound, a "bang" sound, if you will, which I'm sure the actual expansion of space and time did not produce. Now, whether or not you'd like to use metaphorical terms to describe a scientific event is up to you. Quite frankly, seeing that we are in an Internet forum and not some scientific conference, it's perfectly appropriate to use the word explosion. IMO. I don't feel a need to be corrected because I was not implying that there was any sort of traditional, oxygen-based combustion. Visually, most people will try and associate the Bing Bang with an explosion, because it's probably pretty appropriate to do so, because it is in fact an explosion. I understand your point that, in strict scientific terms, an explosion involves the reaction of chemical elements which were not present during the Big Bang. But most people will just be satisfied with the idea of an explosion, because anybody smart enough to realize what an explosion really is will be smart enough to figure out what the Big Bang really consisted of.
Anyway, I'm glad we had this talk, now I can rid my mind of this discussion and contemplate much more important things like when I will be clipping my toenails.