Who is chasing the chasers ?

Do I even understand the words I use? In the last post, I mentioned the word "chaser". An online dictionary, has many definitions of chaser.  These all involve spirits with another drink, but sometimes the spirit is the chaser and some times it is the other drink.

As part of my research for this post i found this useful information.  I had this horror that I would be regarded as uncultured, because I ordered a beer with whisky chaser, but really I should have ordered a whisky with a beer chaser. You may not thing this matters, but the upper class worry which direction the bottle of port is passed.